Catalyst 2970 Switch Command Reference, 12.1(14)EA1
Cisco IOS Commands - aaa through remote-span

Table Of Contents

Cisco IOS Commands

aaa authentication dot1x

action

archive download-sw

archive tar

archive upload-sw

auto qos voip

boot boothlpr

boot config-file

boot enable-break

boot helper

boot helper-config-file

boot manual

boot private-config-file

boot system

channel-group

channel-protocol

class

class-map

clear lacp

clear mac-address-table

clear pagp

clear setup express

clear spanning-tree counters

clear spanning-tree detected-protocols

clear vmps statistics

clear vtp counters

cluster commander-address

cluster discovery hop-count

cluster enable

cluster holdtime

cluster member

cluster outside-interface

cluster run

cluster standby-group

cluster timer

define interface-range

delete

deny

dot1x default

dot1x guest-vlan

dot1x host-mode

dot1x initialize

dot1x max-req

dot1x multiple-hosts

dot1x port-control

dot1x re-authenticate

dot1x re-authentication

dot1x reauthentication

dot1x system-auth-control

dot1x timeout

duplex

errdisable detect cause

errdisable recovery

flowcontrol

interface port-channel

interface range

interface vlan

ip access-group

ip address

ip igmp filter

ip igmp max-groups

ip igmp profile

ip igmp snooping

lacp port-priority

lacp system-priority

logging file

mac access-group

mac access-list extended

mac-address-table aging-time

mac-address-table notification

mac-address-table static

match (access-map configuration)

match (class-map configuration)

mdix auto

mls qos

mls qos aggregate-policer

mls qos cos

mls qos dscp-mutation

mls qos map

mls qos queue-set output buffers

mls qos queue-set output threshold

mls qos srr-queue input bandwidth

mls qos srr-queue input buffers

mls qos srr-queue input cos-map

mls qos srr-queue input dscp-map

mls qos srr-queue input priority-queue

mls qos srr-queue input threshold

mls qos srr-queue output cos-map

mls qos srr-queue output dscp-map

mls qos trust

monitor session

mvr (global configuration)

mvr (interface configuration)

pagp learn-method

pagp port-priority

permit

police

police aggregate

policy-map

port-channel load-balance

queue-set

rcommand

remote-span


Cisco IOS Commands


aaa authentication dot1x

Use the aaa authentication dot1x global configuration command to specify one or more authentication, authorization, and accounting (AAA) methods for use on interfaces running IEEE 802.1X. Use the no form of this command to disable authentication.

aaa authentication dot1x {default} method1 [method2...]

no aaa authentication dot1x {default}

Syntax Description

default

Use the listed authentication methods that follow this argument as the default list of methods when a user logs in.

method1 [method2...]

At least one of the these keywords:

enable—Use the enable password for authentication.

group radius—Use the list of all Remote Authentication Dial-In User Service (RADIUS) servers for authentication.

line—Use the line password for authentication.

local—Use the local username database for authentication.

local-case—Use the case-sensitive local username database for authentication.

none—Use no authentication. The client is automatically authenticated by the switch without using the information supplied by the client.



Note Though visible in the command-line help strings, the group tacacs+ keyword is not supported.


Defaults

No authentication is performed.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

The method argument identifies the list of methods that the authentication algorithm tries in the given sequence to validate the password provided by the client. The only method that is truly 802.1X-compliant is the group radius method, in which the client data is validated against a RADIUS authentication server. The remaining methods enable AAA to authenticate the client by using locally configured data. For example, the local and local-case methods use the username and password that are saved in the IOS configuration file. The enable and line methods use the enable and line passwords for authentication.

If you specify group radius, you must configure the RADIUS server by entering the radius-server host global configuration command.

If you are not using a RADIUS server, you can use the local or local-case methods, which access the local username database to perform authentication. By specifying the enable or line methods, you can supply the clients with a password to provide access to the switch.

Use the show running-config privileged EXEC command to display the configured lists of authentication methods.

Examples

This example shows how to enable AAA and how to create an authentication list for 802.1X. This authentication first tries to contact a RADIUS server. If this action returns an error, the user is allowed access with no authentication.

Switch(config)# aaa new-model
Switch(config)# aaa authentication dot1x default group radius none

You can verify your settings by entering the show running-config privileged EXEC command.

Related Commands

Command
Description

aaa new-model

Enables the AAA access control model. For syntax information, refer to the Cisco IOS Security Command Reference for Release 12.1 > Authentication, Authorization, and Accounting > Authentication Commands.

show running-config

Displays the current operating configuration. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


action

Use the action access map configuration command to set the action for the VLAN access map entry. Use the no form of this command to set the action to the default value, which is to forward.

action {drop | forward}

no action

Syntax Description

drop

Drop the packet when the specified conditions are matched.

forward

Forward the packet when the specified conditions are matched.


Defaults

The default action is to forward packets.

Command Modes

Access-map configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You enter access-map configuration mode by using the vlan access-map global configuration command.

If the action is drop, you should define the access map, including configuring any access control list (ACL) names in match clauses, before applying the map to a VLAN, or all packets could be dropped.

In access map configuration mode, use the match access map configuration command to define the match conditions for a VLAN map. Use the action command to set the action that occurs when a packet matches the conditions.

The drop and forward parameters are not used in the no form of the command.

Examples

This example shows how to identify and apply a VLAN access map vmap4 to VLANs 5 and 6 that causes the VLAN to forward an IP packet if the packet matches the conditions defined in access list al2:

Switch(config)# vlan access-map vmap4
Switch(config-access-map)# match ip address al2
Switch(config-access-map)# action forward
Switch(config-access-map)# exit
Switch(config)# vlan filter vmap4 vlan-list 5-6

You can verify your settings by entering the show vlan access-map privileged EXEC command.

Related Commands

Command
Description

access-list {deny | permit}

Configures a standard numbered ACL. For syntax information, select Cisco IOS IP and IP Routing Command Reference for IOS Release 12.1 > IP Addressing and Services > IP Services Commands.

ip access-list

Creates a named access list. For syntax information, select Cisco IOS IP and IP Routing Command Reference for IOS Release 12.1 > IP Addressing and Services > IP Services Commands.

mac access-list extended

Creates a named MAC address access list.

match (access-map configuration)

Defines the match conditions for a VLAN map.

show vlan access-map

Displays the VLAN access maps created on the switch.

vlan access-map

Creates a VLAN access map.


archive download-sw

Use the archive download-sw privileged EXEC command to download a new image to the switch and to overwrite or keep the existing image.

archive download-sw {/force-reload | /imageonly | /leave-old-sw | /no-set-boot | /overwrite | /reload | /safe} source-url

Syntax Description

/force-reload

Unconditionally force a system reload after successfully downloading the software image.

/imageonly

Download only the software image but not the HTML files associated with the Cluster Management Suite (CMS). The HTML files for the existing version are deleted only if the existing version is being overwritten or removed.

/leave-old-sw

Keep the old software version after a successful download.

/no-set-boot

Do not alter the setting of the BOOT environment variable to point to the new software image after it is successfully downloaded.

/overwrite

Overwrite the software image in Flash memory with the downloaded one.

/reload

Reload the system after successfully downloading the image unless the configuration has been changed and not been saved.

/safe

Keep the current software image; do not delete it to make room for the new software image before the new image is downloaded. The current image is deleted after the download.

source-url

The source URL alias for a local or network file system. These options are supported:

The syntax for the local Flash file system:
flash:

The syntax for the File Transfer Protocol (FTP): ftp:[[//username[:password]@location]/directory]/image-name.tar

The syntax for the Remote Copy Protocol (RCP): rcp:[[//username@location]/directory]/image-name.tar

The syntax for the Trivial File Transfer Protocol (TFTP): tftp:[[//location]/directory]/image-name.tar

The image-name.tar is the software image to download and install on the switch.


Defaults

The current software image is not overwritten with the downloaded image.

Both the software image and HTML files are downloaded.

The new image is downloaded to the flash: file system.

The BOOT environment variable is changed to point to the new software image on the flash: file system.

Image names are case sensitive; the image file is provided in tar format.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

The /imageonly option removes the HTML files for the existing image if the existing image is being removed or replaced. Only the IOS image (without the HTML files) is downloaded.

Using the /safe or /leave-old-sw option can cause the new image download to fail if there is insufficient Flash memory. If leaving the software in place prevents the new image from fitting in Flash memory due to space constraints, an error results.

If you used the /leave-old-sw option and did not overwrite the old image when you downloaded the new one, you can remove the old image by using the delete privileged EXEC command. For more information, see the "delete" section.

Use the /overwrite option to overwrite the image on the Flash device with the downloaded one.

If you specify the command without the /overwrite option, the download algorithm verifies that the new image is not the same as the one on the switch Flash device. If the images are the same, the download does not occur. If the images are different, the old image is deleted, and the new one is downloaded.

After downloading a new image, enter the reload privileged EXEC command to begin using the new image, or specify the /reload or /force-reload option in the archive download-sw command.

Examples

This example shows how to download a new image from a TFTP server at 172.20.129.10 and overwrite the image on the switch:

Switch# archive download-sw /overwrite tftp://172.20.129.10/test-image.tar 

This example shows how to download only the software image from a TFTP server at 172.20.129.10 to the switch:

Switch# archive download-sw /image-only tftp://172.20.129.10/test-image.tar 

This example shows how to keep the old software version after a successful download:

Switch# archive download-sw /leave-old-sw tftp://172.20.129.10/test-image.tar 

Related Commands

Command
Description

archive tar

Creates a tar file, lists the files in a tar file, or extracts the files from a tar file.

archive upload-sw

Uploads an existing image on the switch to a server.

delete

Deletes a file or directory on the Flash memory device.


archive tar

Use the archive tar privileged EXEC command to create a tar file, list files in a tar file, or extract the files from a tar file.

archive tar {/create destination-url flash:/file-url} | {/table source-url} | {/xtract source-url flash:/file-url}

Syntax Description

/create destination-url flash:/file-url

Create a new tar file on the local or network file system.

For destination-url, specify the destination URL alias for the local or network file system and the name of the tar file to create. These options are supported:

The syntax for the local Flash filesystem:
flash:

The syntax for the File Transfer Protocol (FTP): ftp:[[//username[:password]@location]/directory]/tar-filename.tar

The syntax for the Remote Copy Protocol (RCP) is: rcp:[[//username@location]/directory]/tar-filename.tar

The syntax for the Trivial File Transfer Protocol (TFTP): tftp:[[//location]/directory]/tar-filename.tar

The tar-filename.tar is the tar file to be created.

For flash:/file-url, specify the location on the local Flash file system from which the new tar file is created.

An optional list of files or directories within the source directory can be specified to write to the new tar file. If none are specified, all files and directories at this level are written to the newly created tar file.

/table source-url

Display the contents of an existing tar file to the screen.

For source-url, specify the source URL alias for the local or network file system. These options are supported:

The syntax for the local Flash file system:
flash:

The syntax for the File Transfer Protocol (FTP) ftp:[[//username[:password]@location]/directory]/tar-filename.tar

The syntax for the Remote Copy Protocol (RCP): rcp:[[//username@location]/directory]/tar-filename.tar

The syntax for the Trivial File Transfer Protocol (TFTP): tftp:[[//location]/directory]/tar-filename.tar

The tar-filename.tar is the tar file to display.

/xtract source-url flash:/file-url

Extract files from a tar file to the local or network file system.

For source-url, specify the source URL alias for the local or network file system. These options are supported:

The syntax for the local Flash file system:
flash:

The syntax for the File Transfer Protocol (FTP): ftp:[[//username[:password]@location]/directory]/tar-filename.tar

The syntax for the Remote Copy Protocol (RCP): rcp:[[//username@location]/directory]/tar-filename.tar

The syntax for the Trivial File Transfer Protocol (TFTP): tftp:[[//location]/directory]/tar-filename.tar

The tar-filename.tar is the tar file from which to extract.

For flash:/file-url, specify the location on the local Flash file system into which the tar file is extracted.

An optional list of files or directories within the tar file can be specified for extraction. If none are specified, all files and directories are extracted.


Defaults

None

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Filenames and directory names are case sensitive.

Image names are case sensitive.

Examples

This example shows how to create a tar file. The command writes the contents of the new-configs directory on the local Flash device to a file named saved.tar on the TFTP server at 172.20.10.30:

Switch# archive tar /create tftp:172.20.10.30/saved.tar flash:/new-configs

This example shows how to display the contents of the c2970-tv0-m.tar file that is in Flash memory. The contents of the tar file are displayed on the screen:

Switch# archive tar /table flash:c2970-tv0-m.tar
info (219 bytes)
c2970-tv0-mz-121/ (directory)
c2970-tv0-mz-121/html/ (directory)
c2970-tv0-mz-121/html/foo.html (0 bytes)
c2970-tv0-mz-121/vegas-tv0-mz-121.bin (610856 bytes)
c2970-tv0-mz-121/info (219 bytes)
info.ver (219 bytes)

This example shows how to display only the c2970-tv0-mz-121/html directory and its contents:

Switch# archive tar /table flash:c2970-tv0-m.tar c2970-tv0-mz-121/html
c2970-tv0-mz-121/html/ (directory)
c2970-tv0-mz-121/html/foo.html (0 bytes)

This example shows how to extract the contents of a tar file on the TFTP server at 172.20.10.30. This command extracts just the new-configs directory into the root directory on the local Flash file system. The remaining files in the saved.tar file are ignored.

Switch# archive tar /xtract tftp:/172.20.10.30/saved.tar flash:/ new-configs

Related Commands

Command
Description

archive download-sw

Downloads a new image to the switch.

archive upload-sw

Uploads an existing image on the switch to a server.


archive upload-sw

Use the archive upload-sw privileged EXEC command to upload an existing switch image to a server.

archive upload-sw [/version version_string] destination-url

Syntax Description

/version version_string

(Optional) Specify the specific version string of the image to be uploaded.

destination-url

The destination URL alias for a local or network file system. These options are supported:

The syntax for the local Flash file system:
flash:

The syntax for the File Transfer Protocol (FTP): ftp:[[//username[:password]@location]/directory]/image-name.tar

The syntax for the Remote Copy Protocol (RCP): rcp:[[//username@location]/directory]/image-name.tar

The syntax for the Trivial File Transfer Protocol (TFTP): tftp:[[//location]/directory]/image-name.tar

The image-name.tar is the name of software image to be stored on the server.


Defaults

Uploads the currently running image from the flash: file system.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

The upload feature is available only if the HTML files associated with the Cluster Management Suite (CMS) have been installed with the existing image.

The files are uploaded in this sequence: the IOS image, the HTML files, and info. After these files are uploaded, the software creates the tar file.

Image names are case sensitive.

Examples

This example shows how to upload the currently running image to a TFTP server at 172.20.140.2:

Switch# archive upload-sw tftp://172.20.140.2/test-image.tar 

Related Commands

Command
Description

archive download-sw

Downloads a new image to the switch.

archive tar

Creates a tar file, lists the files in a tar file, or extracts the files from a tar file.


auto qos voip

Use the auto qos voip interface configuration command to automatically configure quality of service (QoS) for voice over IP (VoIP) within a QoS domain. Use the no form of this command to return to the default setting.

auto qos voip {cisco-phone | trust}

no auto qos voip [cisco-phone | trust]

Syntax Description

cisco-phone

Identify this interface as connected to a Cisco IP phone, and automatically configure QoS for VoIP. The QoS labels of incoming packets are trusted only when the phone is detected.

trust

Identify this interface as connected to a trusted switch or router, and automatically configure QoS for VoIP. The QoS labels of incoming packets are trusted. For nonrouted interfaces, the CoS value of the incoming packet is trusted.


Defaults

Auto-QoS is disabled on the interface.

When auto-QoS is enabled, it uses the ingress packet label to categorize traffic, to assign packet labels, and to configure the ingress and egress queues as shown in Table 2-1.

Table 2-1 Traffic Types, Ingress Packet Labels, Assigned Packet Labels, and Queues

 
VoIP Data Traffic
VoIP Control
Traffic
Routing Protocol Traffic
STP1 BPDU2 Traffic
All Other Traffic

Ingress DSCP3

46

26

-

-

-

Ingress CoS4

5

3

6

7

-

DiffServ

EF

AF31

-

-

-

Assigned DSCP

46

26

48

56

0

Assigned CoS

5

3

6

7

0

CoS-to-Ingress Queue Map

2, 3, 4, 5, 6, 7 (queue 2)

0, 1 (queue 1)

CoS-to-Egress Queue Map

5 (queue 1)

3, 6, 7 (queue 2)

2, 4 (queue 3)

0, 1 (queue 4)

1 STP = Spanning Tree Protocol

2 BPDU = bridge protocol data unit

3 DSCP = Differentiated Services Code Point

4 CoS = class of service


Table 2-2 shows the generated auto-QoS configuration for the ingress queues.

Table 2-2 Auto-QoS Configuration for the Ingress Queues

Ingress Queue
Queue Number
CoS-to-Queue Map
Queue Weight (Bandwidth)
Queue (Buffer) Size

SRR1 shared

1

0, 1

90 percent

90 percent

Priority

2

2, 3, 4, 5, 6, 7

10 percent

10 percent

1 SRR = shaped round robin. Ingress queues support shared mode only.


Table 2-3 shows the generated auto-QoS configuration for the egress queues.

Table 2-3 Auto-QoS Configuration for the Egress Queues

Egress Queue
Queue Number
CoS-to-Queue Map
Queue Weight (Bandwidth)
Queue (Buffer) Size

Priority (shaped)

1

5

10 percent

20 percent

SRR shared

2

3, 6, 7

10 percent

20 percent

SRR shared

3

2, 4

60 percent

20 percent

SRR shared

4

0, 1

20 percent

40 percent


Command Modes

Interface configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

Use this command to configure the QoS appropriate for VoIP traffic within the QoS domain. The QoS domain includes the switch, the interior of the network, and edge devices that can classify incoming traffic for QoS.

To take advantage of the auto-QoS defaults, you should enable auto-QoS before you configure other QoS commands. You can fine-tune the auto-QoS configuration after you enable auto-QoS.


Note The switch applies the auto-QoS-generated commands as if the commands were entered from the command-line interface (CLI). An existing user configuration can cause the application of the generated commands to fail or to be overridden by the generated commands. These actions occur without warning. If all the generated commands are successfully applied, any user-entered configuration that was not overridden remains in the running configuration. Any user-entered configuration that was overridden can be retrieved by reloading the switch without saving the current configuration to memory. If the generated commands fail to be applied, the previous running configuration is restored.


If this is the first interface on which you have enabled auto-QoS, the auto-QoS-generated global configuration commands are executed followed by the interface configuration commands. If you enable auto-QoS on another interface, only the auto-QoS-generated interface configuration commands for that interface are executed.

When you enable the auto-QoS feature on the first interface, these automatic actions occur:

QoS is globally enabled (mls qos global configuration command), and other global configuration commands are added.

When you enter the auto qos voip cisco-phone interface configuration command on a port at the edge of the network that is connected to a Cisco IP phone, the switch enables the trusted boundary feature. The switch uses the Cisco Discovery Protocol (CDP) to detect the presence or absence of a Cisco IP phone. When a Cisco IP phone is detected, the ingress classification on the interface is set to trust the QoS label received in the packet. When a Cisco IP phone is absent, the ingress classification is set to not trust the QoS label in the packet. The switch configures ingress and egress queues on the interface according to the settings in Table 2-2 and Table 2-3.

When you enter the auto qos voip trust interface configuration command on a port connected to the interior of the network, the switch trusts the CoS value for nonrouted interfaces in ingress packets (the assumption is that traffic has already been classified by other edge devices). The switch configures the ingress and egress queues on the interface according to the settings in Table 2-2 and Table 2-3.

You can enable auto-QoS on static, dynamic-access, and voice VLAN access, and trunk ports.

To display the QoS configuration that is automatically generated when auto-QoS is enabled, enable debugging before you enable auto-QoS. Use the debug autoqos privileged EXEC command to enable auto-QoS debugging. For more information, see the "debug autoqos" section.

To disable auto-QoS on an interface, use the no auto qos voip interface configuration command. Only the auto-QoS-generated interface configuration commands for this interface are removed. If this is the last interface on which auto-QoS is enabled and you enter the no auto qos voip command, auto-QoS is considered disabled even though the auto-QoS-generated global configuration commands remain (to avoid disrupting traffic on other interfaces affected by the global configuration). You can use the no mls qos global configuration command to disable the auto-QoS-generated global configuration commands. With QoS disabled, there is no concept of trusted or untrusted ports because the packets are not modified (the CoS, DSCP, and IP precedence values in the packet are not changed). Traffic is switched in pass-through mode (packets are switched without any rewrites and classified as best effort without any policing).

Examples

This example shows how to enable auto-QoS and to trust the QoS labels received in incoming packets when the switch or router connected to Gigabit Ethernet interface 0/1 is a trusted device:

Switch(config)# interface gigabitethernet0/1
Switch(config-if)# auto qos voip trust

You can verify your settings by entering the show auto qos interface interface-id privileged EXEC command.

Related Commands

Command
Description

debug autoqos

Enables debugging of the auto-QoS feature.

mls qos cos

Defines the default CoS value of a port or assigns the default CoS to all incoming packets on the port.

mls qos map {cos-dscp dscp1 ... dscp8 | dscp-cos dscp-list to cos}

Defines the CoS-to-DSCP map or the DSCP-to-CoS map.

mls qos queue-set output buffers

Allocates buffers to a queue-set.

mls qos srr-queue input bandwidth

Assigns shaped round robin (SRR) weights to an ingress queue.

mls qos srr-queue input buffers

Allocates the buffers between the ingress queues.

mls qos srr-queue input cos-map

Maps CoS values to an ingress queue or maps CoS values to a queue and to a threshold ID.

mls qos srr-queue input dscp-map

Maps DSCP values to an ingress queue or maps DSCP values to a queue and to a threshold ID.

mls qos srr-queue input priority-queue

Configures the ingress priority queue and guarantees bandwidth.

mls qos srr-queue output cos-map

Maps CoS values to an egress queue or maps CoS values to a queue and to a threshold ID.

mls qos srr-queue output dscp-map

Maps DSCP values to an egress queue or maps DSCP values to a queue and to a threshold ID.

mls qos trust

Configures the port trust state.

queue-set

Maps a port to a queue-set.

show auto qos

Displays the initial configuration that is generated by the auto-QoS feature.

show mls qos interface

Displays QoS information at the interface level.

srr-queue bandwidth shape

Assigns the shaped weights and enables bandwidth shaping on the four egress queues mapped to a port.

srr-queue bandwidth share

Assigns the shared weights and enables bandwidth sharing on the four egress queues mapped to a port.


boot boothlpr

Use the boot boothlpr global configuration command to load a special IOS image, which when loaded into memory, can load a second IOS image into memory and launch it. This variable is used only for internal development and testing. Use the no form of this command to return to the default setting.

boot boothlpr filesystem:/file-url

no boot boothlpr

Syntax Description

filesystem:

Alias for a Flash file system. Use flash: for the system board Flash device.

/file-url

The path (directory) and name of a bootable helper image.


Defaults

No helper image is loaded.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Filenames and directory names are case sensitive.

This command changes the setting of the BOOTHLPR environment variable. For more information, see "Boot Loader Commands."

Related Commands

Command
Description

show boot

Displays the settings of the boot environment variables.


boot config-file

Use the boot config-file global configuration command to specify the filename that IOS uses to read and write a nonvolatile copy of the system configuration. Use the no form of this command to return to the default setting.

boot config-file flash:/file-url

no boot config-file

Syntax Description

flash:/file-url

The path (directory) and name of the configuration file.


Defaults

The default configuration file is flash:config.text.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Filenames and directory names are case sensitive.

This command changes the setting of the CONFIG_FILE environment variable. For more information, see "Boot Loader Commands."

Related Commands

Command
Description

show boot

Displays the settings of the boot environment variables.


boot enable-break

Use the boot enable-break global configuration command to enable interrupting the automatic boot process. Use the no form of this command to return to the default setting.

boot enable-break

no boot enable-break

Syntax Description

This command has no arguments or keywords.

Defaults

Disabled. The automatic boot process cannot be interrupted by pressing the Break key on the console.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

When you enter this command, you can interrupt the automatic boot process by pressing the Break key on the console after the Flash file system is initialized.


Note Despite the setting of this command, you can interrupt the automatic boot process at any time by pressing the MODE button on the switch front panel.


This command changes the setting of the ENABLE_BREAK environment variable. For more information, see "Boot Loader Commands."

Related Commands

Command
Description

show boot

Displays the settings of the boot environment variables.


boot helper

Use the boot helper global configuration command to dynamically load files during boot loader initialization to extend or patch the functionality of the boot loader. Use the no form of this command to return to the default.

boot helper filesystem:/file-url ...

no boot helper

Syntax Description

filesystem:

Alias for a Flash file system. Use flash: for the system board Flash device.

/file-url

The path (directory) and a list of loadable files to dynamically load during loader initialization. Separate each image name with a semicolon.


Defaults

No helper files are loaded.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

This variable is used only for internal development and testing.

Filenames and directory names are case sensitive.

This command changes the setting of the HELPER environment variable. For more information, see "Boot Loader Commands."

Related Commands

Command
Description

show boot

Displays the settings of the boot environment variables.


boot helper-config-file

Use the boot helper-config-file global configuration command to specify the name of the configuration file to be used by the IOS helper image. If this is not set, the file specified by the CONFIG_FILE environment variable is used by all versions of IOS that are loaded. Use the no form of this command to return to the default setting.

boot helper-config-file filesystem:/file-url

no boot helper-config file

Syntax Description

filesystem:

Alias for a Flash file system. Use flash: for the system board Flash device.

/file-url

The path (directory) and helper configuration file to load.


Defaults

No helper configuration file is specified.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

This variable is used only for internal development and testing.

Filenames and directory names are case sensitive.

This command changes the setting of the HELPER_CONFIG_FILE environment variable. For more information, see "Boot Loader Commands."

Related Commands

Command
Description

show boot

Displays the settings of the boot environment variables.


boot manual

Use the boot manual global configuration command to enable manually booting the switch during the next boot cycle. Use the no form of this command to return to the default setting.

boot manual

no boot manual

Syntax Description

This command has no arguments or keywords.

Defaults

Manual booting is disabled.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

The next time you reboot the system, the switch is in boot loader mode, which is shown by the switch: prompt. To boot the system, use the boot boot loader command, and specify the name of the bootable image.

This command changes the setting of the MANUAL_BOOT environment variable. For more information, see "Boot Loader Commands."

Related Commands

Command
Description

show boot

Displays the settings of the boot environment variables.


boot private-config-file

Use the boot private-config-file global configuration command to specify the filename that IOS uses to read and write a nonvolatile copy of the private configuration. Use the no form of this command to return to the default setting.

boot private-config-file filename

no boot private-config-file

Syntax Description

filename

The name of the private configuration file.


Defaults

The default configuration file is private-config.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Filenames are case sensitive.

Examples

This example shows how to specify the name of the private configuration file to be pconfig:

Switch(config)# boot private-config-file pconfig

Related Commands

Command
Description

show boot

Displays the settings of the boot environment variables.


boot system

Use the boot system global configuration command to specify the IOS image to load during the next boot cycle. Use the no form of this command to return to the default setting.

boot system filesystem:/file-url ...

no boot system

Syntax Description

filesystem:

Alias for a Flash file system. Use flash: for the system board Flash device.

/file-url

The path (directory) and name of a bootable image. Separate image names with a semicolon.


Defaults

The switch attempts to automatically boot the system by using information in the BOOT environment variable. If this variable is not set, the switch attempts to load and execute the first executable image it can by performing a recursive, depth-first search throughout the Flash file system. In a depth-first search of a directory, each encountered subdirectory is completely searched before continuing the search in the original directory.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Filenames and directory names are case sensitive.

If you are using the archive download-sw privileged EXEC command to maintain system images, you never need to use the boot system command. The boot system command is automatically manipulated to load the downloaded image.

This command changes the setting of the BOOT environment variable. For more information, see "Boot Loader Commands."

Related Commands

Command
Description

show boot

Displays the settings of the boot environment variables.


channel-group

Use the channel-group interface configuration command to assign an Ethernet interface to an EtherChannel group. Use the no form of this command to remove an Ethernet interface from an EtherChannel group.

channel-group channel-group-number mode {active | {auto [non-silent] | desirable [non-silent] | on} | passive}

no channel-group

Syntax Description

channel-group-number

Specify the channel group number. The range is 1 to 12.

mode

Specify the EtherChannel mode of the interface.

active

Unconditionally enable Link Aggregation Protocol (LACP).

Active mode places an interface into a negotiating state in which the interface initiates negotiations with other interfaces by sending LACP packets. A channel is formed with another port group in either the active or passive mode.

auto

Enable the Port Aggregation Protocol (PAgP) only if a PAgP device is detected.

Auto mode places an interface into a passive negotiating state in which the interface responds to PAgP packets it receives but does not start PAgP packet negotiation. A channel is formed only with another port group in desirable mode. When auto is enabled, silent operation is the default.

desirable

Unconditionally enable PAgP.

Desirable mode places an interface into an active negotiating state in which the interface starts negotiations with other interfaces by sending PAgP packets. A channel is formed with another port group in either the desirable or auto mode. When desirable is enabled, silent operation is the default.

non-silent

(Optional) Used with the auto or desirable keyword when traffic is expected from the other device.

on

Force the interface to channel without PAgP or the LACP.

With the on mode, a usable EtherChannel exists only when an interface group in the on mode is connected to another interface group in the on mode.

passive

Enable LACP only if a LACP device is detected.

Passive mode places an interface into a negotiating state in which the interface responds to LACP packets it receives but does not initiate LACP packet negotiation. A channel is formed only with another port group in active mode.


Defaults

No channel groups are assigned.

No mode is configured.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.

12.1(14)EA1

The active and passive keywords were added.


Usage Guidelines

For Layer 2 EtherChannels, you do not have to create a port-channel interface first by using the interface port-channel global configuration command before assigning a physical interface to a channel group. Instead, you can use the channel-group interface configuration command. It automatically creates the port-channel interface when the channel group gets its first physical interface if the logical interface is not already created. If you create the port-channel interface first, the channel-group-number can be the same as the port-channel-number, or you can use a new number. If you use a new number, the channel-group command dynamically creates a new port channel.

After you configure an EtherChannel, configuration changes that you make on the port-channel interface apply to all the physical interfaces assigned to the port-channel interface. Configuration changes applied to the physical interface affect only the interface where you apply the configuration. To change the parameters of all ports in an EtherChannel, apply configuration commands to the port-channel interface, for example, spanning-tree commands or commands to configure a Layer 2 EtherChannel as a trunk.

If you do not specify non-silent with the auto or desirable mode, silent is assumed. The silent mode is used when the switch is connected to a device that is not PAgP-capable and seldom, if ever, sends packets. A example of a silent partner is a file server or a packet analyzer that is not generating traffic. In this case, running PAgP on a physical port prevents that port from ever becoming operational. However, it allows PAgP to operate, to attach the interface to a channel group, and to use the interface for transmission. Both ends of the link cannot be set to silent.

With the on mode, a usable EtherChannel exists only when a port group in the on mode is connected to another port group in the on mode.


Caution You should exercise care when setting the mode to on (manual configuration). All ports configured in the on mode are bundled together in the same group and are forced to have similar characteristics. If the group is misconfigured, packet loss or spanning-tree loops might occur.

Do not configure an EtherChannel in both the PAgP and LACP modes. EtherChannel groups running PAgP and LACP can coexist on the same switch. Individual EtherChannel groups can run either PAgP or LACP, but they cannot interoperate.

If you set the protocol by using the channel-protocol interface configuration command, the setting is not overridden by the channel-group interface configuration command

Do not configure a port that is an active member of an EtherChannel as an 802.1X port. If 802.1X is enabled on a not-yet active port of an EtherChannel, the port does not join the EtherChannel.

Do not configure a secure port as part of an EtherChannel or an EtherChannel port as a secure port.

For a complete list of configuration guidelines, refer to the "Configuring EtherChannels" chapter in the software guide for this release.

Examples

This example shows how to configure EtherChannel. It assigns Gigabit Ethernet interfaces 0/4 and 0/5 as static-access ports in VLAN 10 to channel 5 with the PAgP mode desirable:

Switch# configure terminal 
Switch(config)# interface range gigabitethernet0/4 -5 
Switch(config-if-range)# switchport mode access
Switch(config-if-range)# switchport access vlan 10
Switch(config-if-range)# channel-group 5 mode desirable 
Switch(config-if-range)# end 

This example shows how to configure EtherChannel on a single switch. It assigns Gigabit Ethernet interfaces 0/4 and 0/5 as static-access ports in VLAN 10 to channel 5 with the LACP mode active:

Switch# configure terminal 
Switch(config)# interface range gigabitethernet0/4 -5 
Switch(config-if-range)# switchport mode access
Switch(config-if-range)# switchport access vlan 10
Switch(config-if-range)# channel-group 5 mode active 
Switch(config-if-range)# end 

You can verify your settings by entering the show running-config privileged EXEC command.

Related Commands

Command
Description

channel-protocol

Restricts the protocol used on an interface to manage channeling.

interface port-channel

Accesses or creates the port channel.

show etherchannel

Displays EtherChannel information for a channel.

show lacp

Displays LACP channel-group information.

show pagp

Displays PAgP channel-group information.

show running-config

Displays the current operating configuration. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


channel-protocol

Use the channel-protocol interface configuration command to restrict the protocol used on an interface to manage channeling. Use the no form of this command to return to the default setting.

channel-protocol {lacp | pagp}

no channel-protocol

Syntax Description

lacp

Configure an EtherChannel with the Link Aggregation Control Protocol (LACP).

pagp

Configure an EtherChannel with the Port Aggregation Protocol (PAgP).


Defaults

No protocol is assigned to the EtherChannel.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

Use the channel-protocol command only to restrict a channel to LACP or PAgP. If you set the protocol by using the channel-protocol command, the setting is not overridden by the channel-group interface configuration command.

You must use the channel-group interface configuration command to configure the EtherChannel parameters. The channel-group command also can set the mode for the EtherChannel.

You cannot enable both the PAgP and LACP modes on an EtherChannel group.

PAgP and LACP are not compatible; both ends of a channel must use the same protocol.

Examples

This example shows how to specify LACP as the protocol that manages the EtherChannel:

Switch(config-if)# channel-protocol lacp

You can verify your settings by entering the show etherchannel [channel-group-number] protocol privileged EXEC command.

Related Commands

Command
Description

channel-group

Assigns an Ethernet interface to an EtherChannel group.

show etherchannel protocol

Displays protocol information the EtherChannel.


class

Use the class policy-map configuration command to define a traffic classification match criteria (through the police, set, and trust policy-map class configuration commands) for the specified class-map name. Use the no form of this command to delete an existing class map.

class class-map-name

no class class-map-name

Syntax Description

class-map-name

Name of the class map.


Defaults

No policy map class-maps are defined.

Command Modes

Policy-map configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Before using the class command, you must use the policy-map global configuration command to identify the policy map and to enter policy-map configuration mode. After specifying a policy map, you can configure a policy for new classes or modify a policy for any existing classes in that policy map. You attach the policy map to an interface by using the service-policy interface configuration command.

After entering the class command, you enter policy-map class configuration mode, and these configuration commands are available:

bandwidth: Although this command is displayed, it is not supported on Catalyst 2970 switches.

exit: exits policy-map class configuration mode and returns to policy-map configuration mode.

no: returns a command to its default setting.

police: defines a policer or aggregate policer for the classified traffic. The policer specifies the bandwidth limitations and the action to take when the limits are exceeded. For more information, see the police and police aggregate policy-map class commands.

set: specifies a value to be assigned to the classified traffic. For more information, see the set command.

trust: defines a trust state for traffic classified with the class or the class-map command. For more information, see the trust command.

To return to policy-map configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.

The class command performs the same function as the class-map global configuration command. Use the class command when a new classification, which is not shared with any other ports, is needed. Use the class-map command when the map is shared among many ports.

Examples

This example shows how to create a policy map called policy1. When attached to the ingress direction, it matches all the incoming traffic defined in class1, sets the IP Differentiated Services Code Point (DSCP) to 10, and polices the traffic at an average rate of 1 Mbps and bursts at 20 KB. Traffic exceeding the profile is marked down to a DSCP value obtained from the policed-DSCP map and then sent.

Switch(config)# policy-map policy1
Switch(config-pmap)# class class1
Switch(config-pmap-c)# set ip dscp 10
Switch(config-pmap-c)# police 1000000 20000 exceed-action policed-dscp-transmit
Switch(config-pmap-c)# exit

You can verify your settings by entering the show policy-map privileged EXEC command.

Related Commands

Command
Description

class-map

Creates a class map to be used for matching packets to the class whose name you specify.

police

Defines a policer for classified traffic.

policy-map

Creates or modifies a policy map that can be attached to multiple interfaces to specify a service policy.

set

Classifies IP traffic by setting a DSCP or IP-precedence value in the packet.

show policy-map

Displays quality of service (QoS) policy maps.

trust

Defines a trust state for the traffic classified through the class policy-map configuration command or the class-map global configuration command.


class-map

Use the class-map global configuration command to create a class map to be used for matching packets to the class whose name you specify and to enter class-map configuration mode. Use the no form of this command to delete an existing class map and to return to global configuration mode.

class-map [match-all | match-any] class-map-name

no class-map [match-all | match-any] class-map-name

Syntax Description

match-all

(Optional) Perform a logical-AND of all matching statements under this class map. All criteria in the class map must be matched.

match-any

(Optional) Perform a logical-OR of the matching statements under this class map. One or more criteria must be matched.

class-map-name

Name of the class map.


Defaults

No class maps are defined.

If neither the match-all or match-any keyword is specified, the default is match-all.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Use this command to specify the name of the class for which you want to create or modify class-map match criteria and to enter class-map configuration mode.

The class-map command and its subcommands are used to define packet classification, marking, and aggregate policing as part of a globally named service policy applied on a per-interface basis.

After you are in quality of service (QoS) class-map configuration mode, these configuration commands are available:

description: describes the class map (up to 200 characters). The show class-map privileged EXEC command displays the description and the name of the class-map.

exit: exits from QoS class-map configuration mode.

match: configures classification criteria. For more information, see the match (class-map configuration) command.

no: removes a match statement from a class map.

rename: renames the current class map. If you rename a class map with a name that is already used, the message A class-map with this name already exists appears.

To define packet classification on a physical-port basis, only one match command per class map is supported. In this situation, the match-all and match-any keywords are equivalent.

Only one access control list (ACL) can be configured in a class map. The ACL can have multiple access control entries (ACEs).

Examples

This example shows how to configure the class map called class1 with one match criterion, which is an access list called 103:

Switch(config)# access-list 103 permit any any dscp 10
Switch(config)# class-map class1
Switch(config-cmap)# match access-group 103
Switch(config-cmap)# exit

This example shows how to delete the class map class1:

Switch(config)# no class-map class1

You can verify your settings by entering the show class-map privileged EXEC command.

Related Commands

Command
Description

class

Defines a traffic classification match criteria (through the police, set, and trust policy-map class configuration commands) for the specified class-map name.

match (class-map configuration)

Defines the match criteria to classify traffic.

policy-map

Creates or modifies a policy map that can be attached to multiple interfaces to specify a service policy.

show class-map

Displays QoS class maps.


clear lacp

Use the clear lacp privileged EXEC command to clear Link Aggregation Control Protocol (LACP) channel-group counters.

clear lacp {channel-group-number counters | counters}

Syntax Description

channel-group-number

(Optional) Channel group number. The range is 1 to 12.

counters

Clear traffic counters.


Defaults

No default is defined.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

You can clear all counters by using the clear lacp counters command, or you can clear only the counters for the specified channel group by using the clear lacp channel-group-number counters command.

Examples

This example shows how to clear all channel-group information:

Switch# clear lacp counters

This example shows how to clear LACP traffic counters for group 4:

Switch# clear lacp 4 counters

You can verify that the information was deleted by entering the show lacp counters or the show lacp 4 counters privileged EXEC command.

Related Commands

Command
Description

show lacp

Displays LACP channel-group information.


clear mac-address-table

Use the clear mac-address-table privileged EXEC command to delete from the MAC address table a specific dynamic address, all dynamic addresses on a particular interface, or all dynamic addresses on a particular VLAN. This command also clears the MAC address notification global counters.

clear mac-address-table {dynamic [address mac-addr | interface interface-id | vlan vlan-id] | notification}

Syntax Description

dynamic

Delete all dynamic MAC addresses.

dynamic address mac-addr

(Optional) Delete the specified dynamic MAC address.

dynamic interface interface-id

(Optional) Delete all dynamic MAC addresses on the specified physical port or port channel.

dynamic vlan vlan-id

(Optional) Delete all dynamic MAC addresses for the specified VLAN. The range is 1 to 4096.

notification

Clear the notifications in the history table and reset the counters.


Defaults

No default is defined.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Examples

This example shows how to remove a specific MAC address from the dynamic address table:

Switch# clear mac-address-table dynamic address 0008.0070.0007

You can verify that the information was deleted by entering the show mac-address-table privileged EXEC command.

Related Commands

Command
Description

mac-address-table notification

Enables the MAC address notification feature.

show mac-address-table

Displays the MAC address table static and dynamic entries.

show mac-address-table notification

Displays the MAC address notification settings for all interfaces or the specified interface.

snmp trap mac-notification

Enables the Simple Network Management Protocol (SNMP) MAC address notification trap on a specific interface.


clear pagp

Use the clear pagp privileged EXEC command to clear Port Aggregation Protocol (PAgP) channel-group information.

clear pagp {channel-group-number counters | counters}

Syntax Description

channel-group-number

(Optional) Channel group number. The range is 1 to 12.

counters

Clear traffic counters.


Defaults

No default is defined.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You can clear all counters by using the clear pagp counters command, or you can clear only the counters for the specified channel group by using the clear pagp channel-group-number counters command.

Examples

This example shows how to clear all channel-group information:

Switch# clear pagp counters

This example shows how to clear PAgP traffic counters for group 10:

Switch# clear pagp 10 counters

You can verify that information was deleted by entering the show pagp privileged EXEC command.

Related Commands

Command
Description

show pagp

Displays PAgP channel-group information.


clear setup express

Use the clear setup express privileged EXEC command to exit Express Setup mode without saving the current configuration.

clear setup express

Syntax Description

This command has no arguments or keywords.

Defaults

No default is defined.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

You can use the clear setup express command to exit Express Setup mode. For example, if you activate Express Setup and then decide to connect to the switch through the console port instead of through an Ethernet port, enter the clear setup express command. The switch exits Express Setup mode. The IP address 10.0.0.1 is no longer valid on the switch, and your connection using this IP address is ended.

This command is available only when the switch is in Express Setup mode.

Examples

This example shows how to exit Express Setup mode:

Switch# clear setup express

You can verify that the switch has exited Express Setup mode by entering the show express setup privileged EXEC command.

Related Commands

Command
Description

setup express

Enables Express Setup mode.

show setup express

Displays if Express Setup mode is active.


clear spanning-tree counters

Use the clear spanning-tree counters privileged EXEC command to clear the spanning-tree counters.

clear spanning-tree counters [interface interface-id]

Syntax Description

interface interface-id

(Optional) Clear all spanning-tree counters on the specified interface. Valid interfaces include physical ports, VLANs, and port channels. The VLAN range is 1 to 4094. The port-channel range is 1 to 12.


Defaults

No default is defined.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

If the interface-id is not specified, spanning-tree counters are cleared for all interfaces.

Examples

This example shows how to clear spanning-tree counters for all interfaces:

Switch# clear spanning-tree counters

Related Commands

Command
Description

show spanning-tree

Displays spanning-tree state information.


clear spanning-tree detected-protocols

Use the clear spanning-tree detected-protocols privileged EXEC command to restart the protocol migration process (force the renegotiation with neighboring switches) on all interfaces or on the specified interface.

clear spanning-tree detected-protocols [interface interface-id]

Syntax Description

interface interface-id

(Optional) Restart the protocol migration process on the specified interface. Valid interfaces include physical ports, VLANs, and port channels. The VLAN range is 1 to 4094. The port-channel range is 1 to 12.


Defaults

No default is defined.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

A switch running the rapid per-VLAN spanning-tree plus (rapid-PVST+) protocol or the Multiple Spanning Tree Protocol (MSTP) supports a built-in protocol migration mechanism that enables it to interoperate with legacy 802.1D switches. If a rapid-PVST+ switch or an MSTP switch receives a legacy 802.1D configuration bridge protocol data unit (BPDU) with the protocol version set to 0, it sends only 802.1D BPDUs on that port. A multiple spanning-tree (MST) switch can also detect that a port is at the boundary of a region when it receives a legacy BPDU, an MST BPDU (version 3) associated with a different region, or a rapid spanning-tree (RST) BPDU (version 2).

However, the switch does not automatically revert to the rapid-PVST+ or the MSTP mode if it no longer receives 802.1D BPDUs because it cannot determine whether the legacy switch has been removed from the link unless the legacy switch is the designated switch. Use the clear spanning-tree detected-protocols command in this situation.

Examples

This example shows how to restart the protocol migration process on an interface:

Switch# clear spanning-tree detected-protocols interface gigabitethernet0/1

Related Commands

Command
Description

show spanning-tree

Displays spanning-tree state information.

spanning-tree link-type

Overrides the default link-type setting and enables rapid spanning-tree transitions to the forwarding state.


clear vmps statistics

Use the clear vmps statistics privileged EXEC command to clear the statistics maintained by the VLAN Query Protocol (VQP) client.

clear vmps statistics

Syntax Description

This command has no arguments or keywords.

Defaults

No default is defined.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Examples

This example shows how to clear VLAN Membership Policy Server (VMPS) statistics:

Switch# clear vmps statistics

You can verify that information was deleted by entering the show vmps statistics privileged EXEC command.

Related Commands

Command
Description

show vmps

Displays the VQP version, reconfirmation interval, retry count, VMPS IP addresses, and the current and primary servers.


clear vtp counters

Use the clear vtp counters privileged EXEC command to clear the VLAN Trunking Protocol (VTP) and pruning counters.

clear vtp counters

Syntax Description

This command has no arguments or keywords.

Defaults

No default is defined.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Examples

This example shows how to clear the VTP counters:

Switch# clear vtp counters

You can verify that information was deleted by entering the show vtp counters privileged EXEC command.

Related Commands

Command
Description

show vtp

Displays general information about the VTP management domain, status, and counters.


cluster commander-address

You do not need to enter this command. The cluster command switch automatically provides its MAC address to cluster member switches when these switches join the cluster. The cluster member switch adds this information and other cluster information to its running configuration file. Use the no form of this global configuration command from the cluster member switch console port to remove the switch from a cluster only during debugging or recovery procedures.

cluster commander-address mac-address [member number name name]

no cluster commander-address

Syntax Description

mac-address

MAC address of the cluster command switch.

member number

(Optional) Number of a configured cluster member switch. The range is 0 to 15.

name name

(Optional) Name of the configured cluster up to 31 characters.


Defaults

The switch is not a member of any cluster.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

This command is available only on the cluster command switch.

A cluster member can have only one cluster command switch.

The cluster member switch retains the identity of the cluster command switch during a system reload by using the mac-address parameter.

You can enter the no form on a cluster member switch to remove it from the cluster during debugging or recovery procedures. You would normally use this command from the cluster member switch console port only when the member has lost communication with the cluster command switch. With normal switch configuration, we recommend that you remove cluster member switches only by entering the no cluster member n global configuration command on the cluster command switch.

When a standby cluster command switch becomes active (becomes the cluster command switch), it removes the cluster commander address line from its configuration.

Examples

This is partial sample output from the running configuration of a cluster member.

Switch(config)# show running-configuration

<output truncated>

cluster commander-address 00e0.9bc0.a500 member 4 name my_cluster

<output truncated>

This example shows how to remove a member from the cluster by using the cluster member console.

Switch # configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Switch(config)# no cluster commander-address

You can verify your settings by entering the show cluster privileged EXEC command.

Related Commands

Command
Description

show cluster

Displays the cluster status and a summary of the cluster to which the switch belongs.


cluster discovery hop-count

Use the cluster discovery hop-count global configuration command on the cluster command switch to set the hop-count limit for extended discovery of candidate switches. Use the no form of this command to return to the default setting.

cluster discovery hop-count number

no cluster discovery hop-count

Syntax Description

number

Number of hops from the cluster edge that the cluster command switch limits the discovery of candidates. The range is 1 to 7.


Defaults

The hop count is set to 3.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

This command is available only on the cluster command switch. This command does not operate on cluster member switches.

If the hop count is set to 1, it disables extended discovery. The cluster command switch discovers only candidates that are one hop from the edge of the cluster. The edge of the cluster is the point between the last discovered cluster member switch and the first discovered candidate switch.

Examples

This example shows how to set hop count limit to 4. This command is executed on the cluster command switch.

Switch(config)# cluster discovery hop-count 4

You can verify your setting by entering the show cluster privileged EXEC command.

Related Commands

Command
Description

show cluster

Displays the cluster status and a summary of the cluster to which the switch belongs.

show cluster candidates

Displays a list of candidate switches.


cluster enable

Use the cluster enable global configuration command on a command-capable switch to enable it as the cluster command switch, assign a cluster name, and to optionally assign a member number to it. Use the no form of the command to remove all members and to make the cluster command switch a candidate switch.

cluster enable name [command-switch-member-number]

no cluster enable

Syntax Description

name

Name of the cluster up to 31 characters. Valid characters include only alphanumerics, dashes, and underscores.

command-switch-member-number

(Optional) Assign a member number to the cluster command switch of the cluster. The range is 0 to 15.


Defaults

The switch is not a cluster command switch.

No cluster name is defined.

The member number is 0 when the switch is the cluster command switch.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Enter this command on any command-capable switch that is not part of any cluster. This command fails if a device is already configured as a member of the cluster.

You must name the cluster when you enable the cluster command switch. If the switch is already configured as the cluster command switch, this command changes the cluster name if it is different from the previous cluster name.

Examples

This example shows how to enable the cluster command switch, name the cluster, and set the cluster command switch member number to 4.

Switch(config)# cluster enable Engineering-IDF4 4

You can verify your setting by entering the show cluster privileged EXEC command on the cluster command switch.

Related Commands

Command
Description

show cluster

Displays the cluster status and a summary of the cluster to which the switch belongs.


cluster holdtime

Use the cluster holdtime global configuration command to set the duration in seconds before a switch (either the command or cluster member switch) declares the other switch down after not receiving heartbeat messages. Use the no form of this command to set the duration to the default value.

cluster holdtime holdtime-in-secs

no cluster holdtime

Syntax Description

holdtime-in-secs

Duration in seconds before a switch (either a command or cluster member switch) declares the other switch down. The range is 1 to 300 seconds.


Defaults

The default holdtime is 80 seconds.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Enter this command with the cluster timer global configuration command only on the cluster command switch. The cluster command switch propagates the values to all its cluster members so that the setting is consistent among all switches in the cluster.

The holdtime is typically set as a multiple of the interval timer (cluster timer). For example, it takes (holdtime-in-secs divided by the interval-in-secs) number of heartbeat messages to be missed in a row to declare a switch down.

Examples

This example shows how to change the interval timer and the duration on the cluster command switch.

Switch(config)# cluster timer 3
Switch(config)# cluster holdtime 30

You can verify your settings by entering the show cluster privileged EXEC command.

Related Commands

Command
Description

show cluster

Displays the cluster status and a summary of the cluster to which the switch belongs.


cluster member

Use the cluster member global configuration command on the cluster command switch to add candidates to a cluster. Use the no form of the command to remove members from the cluster.

cluster member [n] mac-address H.H.H [password enable-password] [vlan vlan-id]

no cluster member n

Syntax Description

n

The number that identifies a cluster member. The range is 0 to 15.

mac-address H.H.H

MAC address of the cluster member switch in hexadecimal format.

password enable-password

Enable password of the candidate switch. The password is not required if there is no password on the candidate switch.

vlan vlan-id

(Optional) VLAN ID through which the candidate is added to the cluster by the cluster command switch. The range is 1 to 4094.


Defaults

A newly enabled cluster command switch has no associated cluster members.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Enter this command only on the cluster command switch to add a candidate to or remove a member from the cluster. If you enter this command on a switch other than the cluster command switch, the switch rejects the command and displays an error message.

You must enter a member number to remove a switch from the cluster. However, you do not need to enter a member number to add a switch to the cluster. The cluster command switch selects the next available member number and assigns it to the switch that is joining the cluster.

You must enter the enable password of the candidate switch for authentication when it joins the cluster. The password is not saved in the running or startup configuration. After a candidate switch becomes a member of the cluster, its password becomes the same as the cluster command-switch password.

If a switch does not have a configured host name, the cluster command switch appends a member number to the cluster command-switch host name and assigns it to the cluster member switch.

If you do not specify a VLAN ID, the cluster command switch automatically chooses a VLAN and adds the candidate to the cluster.

Examples

This example shows how to add a switch as member 2 with MAC address 00E0.1E00.2222 and the password key to a cluster. The cluster command switch adds the candidate to the cluster through VLAN 3.

Switch(config)# cluster member 2 mac-address 00E0.1E00.2222 password key vlan 3

This example shows how to add a switch with MAC address 00E0.1E00.3333 to the cluster. This switch does not have a password. The cluster command switch selects the next available member number and assigns it to the switch that is joining the cluster.

Switch(config)# cluster member mac-address 00E0.1E00.3333

You can verify your settings by entering the show cluster members privileged EXEC command on the cluster command switch.

Related Commands

Command
Description

show cluster

Displays the cluster status and a summary of the cluster to which the switch belongs.

show cluster candidates

Displays a list of candidate switches.

show cluster members

Displays information about the cluster members.


cluster outside-interface

Use the cluster outside-interface global configuration command to configure the outside interface for cluster Network Address Translation (NAT) so that a member without an IP address can communicate with devices outside the cluster. Use the no form of this command to return to the default setting.

cluster outside-interface interface-id

no cluster outside-interface

Syntax Description

interface-id

Interface to serve as the outside interface. Valid interfaces include physical interfaces, port-channels, or VLANs. The port-channel range is 1 to 12. The VLAN range is 1 to 4094.


Defaults

The default outside interface is automatically selected by the cluster command switch.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Enter this command only on the cluster command switch. If you enter this command on a cluster member switch, an error message appears.

Examples

This example shows how to set the outside interface to VLAN 1:

Switch(config)# cluster outside-interface vlan 1

You can verify your setting by entering the show running-config privileged EXEC command.

Related Commands

Command
Description

show running-config

Displays the current operating configuration. For syntax information, select the Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


cluster run

Use the cluster run global configuration command to enable clustering on a switch. Use the no form of this command to disable clustering on a switch.

cluster run

no cluster run

Syntax Description

This command has no arguments or keywords.

Defaults

Clustering is enabled on all switches.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

When you enter the no cluster run command on a cluster command switch, the cluster command switch is disabled. Clustering is disabled, and the switch cannot become a candidate switch.

When you enter the no cluster run command on a cluster member switch, it is removed from the cluster. Clustering is disabled, and the switch cannot become a candidate switch.

When you enter the no cluster run command on a switch that is not part of a cluster, clustering is disabled on this switch. This switch cannot then become a candidate switch.

Examples

This example shows how to disable clustering on the cluster command switch:

Switch(config)# no cluster run

You can verify your setting by entering the show cluster privileged EXEC command.

Related Commands

Command
Description

show cluster

Displays the cluster status and a summary of the cluster to which the switch belongs.


cluster standby-group

Use the cluster standby-group global configuration command to enable cluster command-switch redundancy by binding the cluster to an existing Hot Standby Router Protocol (HSRP). Entering the routing-redundancy keyword enables the same HSRP group to be used for cluster command-switch redundancy and routing redundancy. Use the no form of this command to return to the default setting.

cluster standby-group HSRP-group-name [routing-redundancy]

no cluster standby-group

Syntax Description

HSRP-group-name

Name of the HSRP group that is bound to the cluster. The group name is limited to 32 characters.

routing-redundancy

(Optional) Enable the same HSRP standby group to be used for cluster command-switch redundancy and routing redundancy.


Defaults

The cluster is not bound to any HSRP group.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Enter this command only on the cluster command switch. If you enter it on a cluster member switch, an error message appears.

The cluster command switch propagates the cluster-HSRP binding information to all cluster-HSRP capable members. Each cluster member switch stores the binding information in its nonvolatile RAM (NVRAM).

The HSRP group name must be a valid standby group; otherwise, the command exits with an error.

The same group name should be used on all members of the HSRP standby group that is to be bound to the cluster. The same HSRP group name should also be used on all cluster-HSRP capable members for the HSRP group that is to be bound. (When not binding a cluster to an HSRP group, you can use different names on the cluster commander and the members.)

Examples

This example shows how to bind the HSRP group named my_hsrp to the cluster. This command is executed on the cluster command switch.

Switch(config)# cluster standby-group my_hsrp 

This example shows how to use the same HSRP group named my_hsrp for routing redundancy and cluster redundancy.

Switch(config)# cluster standby-group my_hsrp routing-redundancy

This example shows the error message when this command is executed on a cluster command switch and the specified HSRP standby group does not exist:

Switch(config)# cluster standby-group my_hsrp 
%ERROR: Standby (my_hsrp) group does not exist

This example shows the error message when this command is executed on a cluster member switch:

Switch(config)# cluster standby-group my_hsrp routing-redundancy
%ERROR: This command runs on a cluster command switch

You can verify your settings by entering the show cluster privileged EXEC command. The output shows whether redundancy is enabled in the cluster.

Related Commands

Command
Description

standby ip

Enables HSRP on the interface. For syntax information, select Cisco IOS IP and IP Routing Command Reference for IOS Release 12.1 > IP Addressing and Services > IP Services Commands.

show cluster

Displays the cluster status and a summary of the cluster to which the switch belongs.

show standby

Displays standby group information. For syntax information, select Cisco IOS IP and IP Routing Command Reference for IOS Release 12.1 > IP Addressing and Services > IP Services Commands.


cluster timer

Use the cluster timer global configuration command to set the interval in seconds between heartbeat messages. Use the no form of this command to set the interval to the default value.

cluster timer interval-in-secs

no cluster timer

Syntax Description

interval-in-secs

Interval in seconds between heartbeat messages. The range is 1 to 300 seconds.


Defaults

The interval is 8 seconds.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Enter this command with the cluster holdtime global configuration command only on the cluster command switch. The cluster command switch propagates the values to all its cluster members so that the setting is consistent among all switches in the cluster.

The holdtime is typically set as a multiple of the heartbeat interval timer (cluster timer). For example, it takes (holdtime-in-secs divided by the interval-in-secs) number of heartbeat messages to be missed in a row to declare a switch down.

Examples

This example shows how to change the heartbeat interval timer and the duration on the cluster command switch:

Switch(config)# cluster timer 3
Switch(config)# cluster holdtime 30

You can verify your settings by entering the show cluster privileged EXEC command.

Related Commands

Command
Description

show cluster

Displays the cluster status and a summary of the cluster to which the switch belongs.


define interface-range

Use the define interface-range global configuration command to create an interface-range macro. Use the no form of this command to delete the defined macro.

define interface-range macro-name interface-range

no define interface-range macro-name interface-range

Syntax Description

macro-name

Name of the interface-range macro; up to 32 characters.

interface-range

Interface range; for valid values for interface ranges, see "Usage Guidelines."


Defaults

This command has no default setting.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

The macro name is a 32-character maximum character string.

A macro can contain up to five ranges.

All interfaces in a range must be the same type; that is, all Gigabit Ethernet ports, all EtherChannel ports, or all VLANs, but you can combine multiple interface types in a macro.

When entering the interface-range, use this format:

type {first-interface} - {last-interface}

You must add a space between the first interface number and the hyphen when entering an interface-range. For example, gigabitethernet0/1 -5 is a valid range; gigabitethernet0/1-5 is not a valid range.

Valid values for type and interface:

vlan vlan-id, where vlan-id is from 1 to 4094

VLAN interfaces must have been configured with the interface vlan command (the show running-config privileged EXEC command displays the configured VLAN interfaces). VLAN interfaces not displayed by the show running-config command cannot be used in interface-ranges.

port-channel port-channel-number, where port-channel-number is from 1 to 12

gigabitethernet module/{first port} - {last port}

For physical interfaces:

module is always 0

the range is type 0/number - number (for example, gigabitethernet 0/1 - 2)

When you define a range, you must enter a space before the hyphen (-), for example:

gigabitethernet0/1 - 2

You can also enter multiple ranges. When you define multiple ranges, you must enter a space after the first entry before the comma (,). The space after the comma is optional, for example:

gigabitethernet0/3 ,gigabitethernet 0/6 - 7

gigabitethernet0/3 -4 , gigabitethernet 0/6 - 7

Examples

This example shows how to create a multiple-interface macro:

Switch(config)# define interface-range macro1 gigabitethernet0/1 -2 , gigabitethernet0/5 

Related Commands

Command
Description

interface range

Executes a command on multiple ports at the same time.

show running-config

Displays the current operating configuration, including defined macros. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


delete

Use the delete privileged EXEC command to delete a file or directory on the Flash memory device.

delete [/force] [/recursive] filesystem:/file-url

Syntax Description

/force

(Optional) Suppress the prompt that confirms the deletion.

/recursive

(Optional) Delete the named directory and all subdirectories and the files contained in it.

filesystem:

Alias for a Flash file system.

The syntax for the local Flash file system:
flash:

 

/file-url

The path (directory) and filename to delete.


Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

If you use the /force keyword, you are prompted once at the beginning of the deletion process to confirm the deletion.

If you use the /recursive keyword without the /force keyword, you are prompted to confirm the deletion of every file.

The prompting behavior depends on the setting of the file prompt global configuration command. By default, the switch prompts for confirmation on destructive file operations. For more information about this command, refer to the Cisco IOS Command Reference for Release 12.1.

Examples

This example shows how to remove the directory that contains the old software image after a successful download of a new image:

Switch# delete /force /recursive flash:/old-image

You can verify that the directory was removed by entering the dir filesystem: privileged EXEC command.

Related Commands

Command
Description

archive download-sw

Downloads a new image to the switch and overwrites or keeps the existing image.


deny

Use the deny MAC access list configuration command to prevent non-IP traffic from being forwarded if the conditions are matched. Use the no form of this command to remove a deny condition from the named MAC access list.

{deny | permit} {any | host src-MAC-addr | src-MAC-addr mask} {any | host dst-MAC-addr | dst-MAC-addr mask} [type mask | aarp | amber | cos cos | dec-spanning | decnet-iv | diagnostic | dsm | etype-6000 | etype-8042 | lat | lavc-sca | lsap lsap mask |mop-console | mop-dump | msdos | mumps | netbios | vines-echo | vines-ip | xns-idp]

no {deny | permit} {any | host src-MAC-addr | src-MAC-addr mask} {any | host dst-MAC-addr | dst-MAC-addr mask} [type mask | aarp | amber | cos cos | dec-spanning | decnet-iv | diagnostic | dsm | etype-6000 | etype-8042 | lat | lavc-sca | lsap lsap mask | mop-console | mop-dump | msdos | mumps | netbios | vines-echo | vines-ip | xns-idp]

Syntax Description

any

Keyword to specify to deny any source or destination MAC address.

host src MAC-addr |
src-MAC-addr mask

Define a host MAC address and optional subnet mask. If the source address for a packet matches the defined address, non-IP traffic from that address is denied.

host dst-MAC-addr |
dst-MAC-addr mask

Define a destination MAC address and optional subnet mask. If the destination address for a packet matches the defined address, non-IP traffic to that address is denied.

type mask

(Optional) Use the Ethertype number of a packet with Ethernet II or SNAP encapsulation to identify the protocol of the packet.

The type is 0 to 65535, specified in hexadecimal.

The mask is a mask of don't care bits applied to the Ethertype before testing for a match.

aarp

(Optional) Select Ethertype AppleTalk Address Resolution Protocol that maps a data-link address to a network address.

amber

(Optional) Select EtherType DEC-Amber.

cos cos

(Optional) Select a class of service (CoS) number from 0 to 7 to set priority. Filtering on CoS can be performed only in hardware. A warning message reminds the user if the cos option is configured.

dec-spanning

(Optional) Select EtherType Digital Equipment Corporation (DEC) spanning tree.

decnet-iv

(Optional) Select EtherType DECnet Phase IV protocol.

diagnostic

(Optional) Select EtherType DEC-Diagnostic.

dsm

(Optional) Select EtherType DEC-DSM.

etype-6000

(Optional) Select EtherType 0x6000.

etype-8042

(Optional) Select EtherType 0x8042.

lat

(Optional) Select EtherType DEC-LAT.

lavc-sca

(Optional) Select EtherType DEC-LAVC-SCA.

lsap lsap-number mask

(Optional) Use the LSAP number (0 to 65535) of a packet with 802.2 encapsulation to identify the protocol of the packet.

mask is a mask of don't care bits applied to the LSAP number before testing for a match.

mop-console

(Optional) Select EtherType DEC-MOP Remote Console.

mop-dump

(Optional) Select EtherType DEC-MOP Dump.

msdos

(Optional) Select EtherType DEC-MSDOS.

mumps

(Optional) Select EtherType DEC-MUMPS.

netbios

(Optional) Select EtherType DEC- Network Basic Input/Output System (NETBIOS).

vines-echo

(Optional) Select EtherType Virtual Integrated Network Service (VINES) Echo from Banyan Systems.

vines-ip

(Optional) Select EtherType VINES IP.

xns-idp

(Optional) Select EtherType Xerox Network Systems (XNS) protocol suite (0 to 65535), an arbitrary Ethertype in decimal, hexadecimal, or octal.



Note Though visible in the command-line help strings, appletalk is not supported as a matching condition.


To filter IPX traffic, you use the type mask or lsap lsap mask keywords, depending on the type of IPX encapsulation being used. Filter criteria for IPX encapsulation types as specified in Novell terminology and Cisco IOS terminology are listed in Table 2-4.

Table 2-4 IPX Filtering Criteria

IPX Encapsulation Type
Filter Criterion
Cisco IOS Name
Novel Name

arpa

Ethernet II

Ethertype 0x8137

snap

Ethernet-snap

Ethertype 0x8137

sap

Ethernet 802.2

LSAP 0xE0E0

novell-ether

Ethernet 802.3

LSAP 0xFFFF


Defaults

This command has no defaults. However; the default action for a MAC-named ACL is to deny.

Command Modes

MAC-access list configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You enter MAC-access list configuration mode by using the mac access-list extended global configuration command.

If you use the host keyword, you cannot enter an address mask; if you do not use the host keyword, you must enter an address mask.

When an access control entry (ACE) is added to an access control list, an implied deny-any-any condition exists at the end of the list. That is, if there are no matches, the packets are denied. However, before the first ACE is added, the list permits all packets.


Note For more information about named MAC extended access lists, refer to the software configuration guide for this release.


Examples

This example shows how to define the named MAC extended access list to deny NETBIOS traffic from any source to MAC address 00c0.00a0.03fa. Traffic matching this list is denied.

Switch(config-ext-macl)# deny any host 00c0.00a0.03fa netbios.

This example shows how to remove the deny condition from the named MAC extended access list:

Switch(config-ext-macl)# no deny any 00c0.00a0.03fa 0000.0000.0000 netbios.

This example denies all packets with Ethertype 0x4321:

Switch(config-ext-macl)# deny any any 0x4321 0

You can verify your settings by entering the show access-lists privileged EXEC command.

Related Commands

Command
Description

mac access-list extended

Creates an access list based on MAC addresses for non-IP traffic.

permit

Permits non-IP traffic to be forwarded if conditions are matched.

show access-lists

Displays access control lists configured on a switch.


dot1x default

Use the dot1x default interface configuration command to reset the configurable 802.1X parameters to their default values.

dot1x default

Syntax Description

This command has no arguments or keywords.

Defaults

These are the default values:

The per-interface 802.1X protocol enable state is disabled (force-authorized).

The number of seconds between re-authentication attempts is 3600 seconds.

The periodic re-authentication is disabled.

The quiet period is 60 seconds.

The retransmission time is 30 seconds.

The maximum retransmission number is 2 times.

The host mode is single host.

The client timeout period is 30 seconds.

The authentication server timeout period is 30 seconds.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.

12.1(14)EA1

This command was changed to the interface configuration mode.


Examples

This example shows how to reset the configurable 802.1X parameters on an interface:

Switch(config-if)# dot1x default

You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.

Related Commands

Command
Description

show dot1x [interface interface-id]

Displays 802.1X status for the specified interface.


dot1x guest-vlan

Use the dot1x guest-vlan interface configuration command to specify an active VLAN as an 802.1X guest VLAN. Use the no form of this command to return to the default setting.

dot1x guest-vlan vlan-id

no dot1x guest-vlan

Syntax Description

vlan-id

Specify an active VLAN as an 802.1X guest VLAN. The range is 1 to 4094.


Defaults

No guest VLAN is configured.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

When you configure a guest VLAN, clients that are not 802.1X-capable are put into the guest VLAN when the server does not receive a response to its Extensible Authentication Protocol over LAN (EAPOL) request/identity frame. Clients that are 802.1X-capable but fail authentication are not granted access to the network.

Guest VLANs are supported on 802.1X ports in single-host mode and multiple-hosts mode.

You can configure any active VLAN except an RSPAN VLAN or a voice VLAN as an 802.1X guest VLAN. The guest VLAN feature is not supported on trunk ports; it is supported only on access ports.

Examples

This example shows how to specify VLAN 5 as an 802.1X guest VLAN:

Switch(config-if)# dot1x guest-vlan 5

You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.

Related Commands

Command
Description

show dot1x [interface interface-id]

Displays 802.1X status for the specified interface.


dot1x host-mode

Use the dot1x host-mode interface configuration command to allow a single host (client) or multiple hosts on an 802.1X-authorized port that has the dot1x port-control interface configuration command set to auto. Use the no form of this command to return to the default setting.

dot1x host-mode {multi-host | single-host}

no dot1x host-mode [multi-host | single-host]

Syntax Description

multi-host

Enable multiple-hosts mode on the switch.

single-host

Enable single-host mode on the switch.


Defaults

The default is single-host mode.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced. It replaces the dot1x multiple-hosts interface configuration command.


Usage Guidelines

Use this command to limit an 802.1X-enabled port to a single client or to attach multiple clients to an 802.1X-enabled port. In multiple-hosts mode, only one of the attached hosts must be successfully authorized for all hosts to be granted network access. If the port becomes unauthorized (re-authentication fails or an Extensible Authentication Protocol over LAN [EAPOL]-logoff message is received), all attached clients are denied access to the network.

Before entering this command, make sure that the dot1x port-control interface configuration command is set to auto for the specified interface.

Examples

This example shows how to enable 802.1X globally, enable 802.1X on Gigabit Ethernet interface 0/1, and enable multiple-hosts mode:

Switch(config)# dot1x system-auth-control
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# dot1x port-control auto
Switch(config-if)# dot1x host-mode multi-host

You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.

Related Commands

Command
Description

show dot1x [interface interface-id]

Displays 802.1X status for the specified interface.


dot1x initialize

Use the dot1x initialize privileged EXEC command to manually return the specified 802.1X-enabled interface to an unauthorized state before initiating a new authentication session on the interface.

dot1x initialize interface interface-id

Syntax Description

interface interface-id

Interface to be initialized.


Defaults

There is no default setting.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

Use this command to initialize the 802.1X state machines and to set up a fresh environment for authentication. After you enter this command, the port status becomes unauthorized.

There is no no form of this command.

Examples

This example shows how to manually initialize Gigabit Ethernet interface 0/3:

Switch# dot1x initialize interface gigabitethernet0/3

You can verify the unauthorized port status by entering the show dot1x [interface interface-id] privileged EXEC command.

Related Commands

Command
Description

show dot1x [interface interface-id]

Displays 802.1X status for the specified interface.


dot1x max-req

Use the dot1x max-req interface configuration command to set the maximum number of times that the switch sends an Extensible Authentication Protocol (EAP)-request/identity frame (assuming that no response is received) to the client before restarting the authentication process. Use the no form of this command to return to the default setting.

dot1x max-req count

no dot1x max-req

Syntax Description

count

Number of times that the switch sends an EAP-request/identity frame before restarting the authentication process. The range is 1 to 10.


Defaults

The default is 2 times.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.

12.1(14)EA1

This command was changed to the interface configuration mode.


Usage Guidelines

You should change the default value of this command only to adjust for unusual circumstances such as unreliable links or specific behavioral problems with certain clients and authentication servers.

Examples

This example shows how to set 5 as the number of times that the switch sends an EAP-request/identity frame before restarting the authentication process:

Switch(config-if)# dot1x max-req 5

You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.

Related Commands

Command
Description

dot1x timeout tx-period

Sets the number of seconds that the switch waits for a response to an EAP-request/identity frame from the client before resending the request.

show dot1x [interface interface-id]

Displays 802.1X status for the specified interface.


dot1x multiple-hosts

This is an obsolete command.

In past releases, the dot1x multiple-hosts interface configuration command was used to allow multiple hosts (clients) on an 802.1X-authorized port.

Command History

Release
Modification

12.1(11)AX

This command was first introduced.

12.1(14)EA1

The dot1x multiple-hosts interface configuration command was replaced by the dot1x host-mode interface configuration command.


Related Commands

Command
Description

dot1x host-mode

Sets the 802.1X host mode on an interface.

show dot1x

Displays 802.1X statistics, administrative status, and operational status for the switch or for the specified interface.


dot1x port-control

Use the dot1x port-control interface configuration command to enable manual control of the authorization state of the port. Use the no form of this command to return to the default setting.

dot1x port-control {auto | force-authorized | force-unauthorized}

no dot1x port-control

Syntax Description

auto

Enable 802.1X authentication on the interface and cause the port to transition to the authorized or unauthorized state based on the 802.1X authentication exchange between the switch and the client.

force-authorized

Disable 802.1X authentication on the interface and cause the port to transition to the authorized state without any authentication exchange required. The port sends and receives normal traffic without 802.1X-based authentication of the client.

force-unauthorized

Deny all access through this interface by forcing the port to transition to the unauthorized state, ignoring all attempts by the client to authenticate. The switch cannot provide authentication services to the client through the interface.


Defaults

The default is force-authorized.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You must globally enable 802.1X on the switch by using the dot1x system-auth-control global configuration command before enabling 802.1X on a specific interface.

The 802.1X protocol is supported on Layer 2 static-access ports and voice VLAN ports.

You can use the auto keyword only if the port is not configured as one of these:

Trunk port—If you try to enable 802.1X on a trunk port, an error message appears, and 802.1X is not enabled. If you try to change the mode of an 802.1X-enabled port to trunk, an error message appears, and the port mode is not changed.

Dynamic ports—A port in dynamic mode can negotiate with its neighbor to become a trunk port. If you try to enable 802.1X on a dynamic port, an error message appears, and 802.1X is not enabled. If you try to change the mode of an 802.1X-enabled port to dynamic, an error message appears, and the port mode is not changed.

Dynamic-access ports—If you try to enable 802.1X on a dynamic-access (VLAN Query Protocol [VQP]) port, an error message appears, and 802.1X is not enabled. If you try to change an 802.1X-enabled port to dynamic VLAN assignment, an error message appears, and the VLAN configuration is not changed.

EtherChannel port—Before enabling 802.1X on the port, you must first remove it from the EtherChannel. If you try to enable 802.1X on an EtherChannel or on an active port in an EtherChannel, an error message appears, and 802.1X is not enabled. If you enable 802.1X on a not-yet active port of an EtherChannel, the port does not join the EtherChannel.

Switched Port Analyzer (SPAN) and Remote SPAN (RSPAN) destination ports—You can enable 802.1X on a port that is a SPAN or RSPAN destination port. However, 802.1X is disabled until the port is removed as a SPAN or RSPAN destination. You can enable 802.1X on a SPAN or RSPAN source port.

To globally disable 802.1X on the switch, use the no dot1x system-auth-control global configuration command. To disable 802.1X on a specific interface, use the no dot1x port-control interface configuration command.

Examples

This example shows how to enable 802.1X on Gigabit Ethernet interface 0/1:

Switch(config)# interface gigabitethernet0/1
Switch(config-if)# dot1x port-control auto

You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.

Related Commands

Command
Description

show dot1x [interface interface-id]

Displays 802.1X status for the specified interface.


dot1x re-authenticate

Use the dot1x re-authenticate privileged EXEC command to manually initiate a re-authentication of all 802.1X-enabled ports or the specified 802.1X-enabled port.

dot1x re-authenticate interface interface-id

Syntax Description

interface interface-id

Module and port number of the interface to re-authenticate.


Defaults

There is no default setting.

Command Modes

Privileged EXEC

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You can use this command to re-authenticate a client without waiting for the configured number of seconds between re-authentication attempts (re-authperiod) and automatic re-authentication.

Examples

This example shows how to manually re-authenticate the device connected to Gigabit Ethernet interface 0/1:

Switch# dot1x re-authenticate interface gigabitethernet0/1

dot1x re-authentication

This is an obsolete command.

In past releases, the dot1x re-authentication global configuration command was used to set the amount of time between periodic re-authentication attempts.

Command History

Release
Modification

12.1(11)AX

This command was first introduced.

12.1(14)EA1

The dot1x reauthentication interface configuration command replaced the dot1x re-authentication global configuration command.


Related Commands

Command
Description

dot1x reauthentication

Sets the number of seconds between re-authentication attempts.

show dot1x

Displays 802.1X statistics, administrative status, and operational status for the switch or for the specified interface.


dot1x reauthentication

Use the dot1x reauthentication interface configuration command to enable periodic re-authentication of the client. Use the no form of this command to return to the default setting.

dot1x reauthentication

no dot1x reauthentication

Syntax Description

This command has no arguments or keywords.

Defaults

Periodic re-authentication is disabled.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced. It replaces the dot1x re-authentication global configuration command (with the hyphen).


Usage Guidelines

You configure the amount of time between periodic re-authentication attempts by using the dot1x timeout reauth-period interface configuration command.

Examples

This example shows how to disable periodic re-authentication of the client:

Switch(config-if)# no dot1x reauthentication

This example shows how to enable periodic re-authentication and to set the number of seconds between re-authentication attempts to 4000 seconds:

Switch(config-if)# dot1x reauthentication
Switch(config-if)# dot1x timeout reauth-period 4000

You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.

Related Commands

Command
Description

dot1x timeout reauth-period

Sets the number of seconds between re-authentication attempts.

show dot1x [interface interface-id]

Displays 802.1X status for the specified interface.


dot1x system-auth-control

Use the dot1x system-auth-control global configuration command to globally enable 802.1X. Use the no form of this command to return to the default setting.

dot1x system-auth-control

no dot1x system-auth-control

Syntax Description

This command has no arguments or keywords.

Defaults

802.1X is disabled.

Command Modes

Global configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

You must enable authentication, authorization, and accounting (AAA) and specify the authentication method list before globally enabling 802.1X. A method list describes the sequence and authentication methods to be queried to authenticate a user.

Examples

This example shows how to globally enable 802.1X on a switch:

Switch(config)# dot1x system-auth-control

You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.

Related Commands

Command
Description

dot1x port-control

Enables manual control of the authorization state of the port.

show dot1x [interface interface-id]

Displays 802.1X status for the specified interface.


dot1x timeout

Use the dot1x timeout interface configuration command to set 802.1X timers. Use the no form of this command to return to the default setting.

dot1x timeout {quiet-period seconds | reauth-period seconds | server-timeout seconds | supp-timeout seconds | tx-period seconds}

no dot1x timeout {quiet-period | reauth-period | server-timeout | supp-timeout | tx-period}

Syntax Description

quiet-period seconds

Number of seconds that the switch remains in the quiet state following a failed authentication exchange with the client. The range is 1 to 65535.

reauth-period seconds

Number of seconds between re-authentication attempts. The range is 1 to 65535.

server-timeout seconds

Number of seconds that the switch waits for the retransmission of packets by the switch to the authentication server. The range is 1 to 65535.

supp-timeout seconds

Number of seconds that the switch waits for the retransmission of packets by the switch to the 802.1X client. The range is 1 to 65535.

tx-period seconds

Number of seconds that the switch waits for a response to an EAP-request/identity frame from the client before retransmitting the request. The range is 1 to 65535.


Defaults

These are the default settings:

reauth-period is 3600 seconds.

quiet-period is 60 seconds.

tx-period is 30 seconds.

supp-timeout is 30 seconds.

server-timeout is 30 seconds.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.

12.1(14)EA1

The supp-timeout and server-timeout keywords were added, and the command was changed to the interface configuration mode.


Usage Guidelines

You should change the default value of this command only to adjust for unusual circumstances such as unreliable links or specific behavioral problems with certain clients and authentication servers.

The dot1x timeout reauth-period interface configuration command affects the behavior of the switch only if you have enabled periodic re-authentication by using the dot1x reauthentication interface configuration command.

During the quiet period, the switch does not accept or initiate any authentication requests. If you want to provide a faster response time to the user, enter a smaller number than the default.

Examples

This example shows how to enable periodic re-authentication and to set 4000 as the number of seconds between re-authentication attempts:

Switch(config-if)# dot1x reauthentication
Switch(config-if)# dot1x timeout reauth-period 4000

This example shows how to set 30 seconds as the quiet time on the switch:

Switch(config-if)# dot1x timeout quiet-period 30

This example shows how to set 25 seconds as the switch-to-authentication server retransmission time:

Switch(config)# dot1x timeout server-timeout 25

This example shows how to set 25 seconds as the switch-to-client retransmission time for the EAP request frame:

Switch(config-if)# dot1x timeout supp-timeout 25

This example shows how to set 60 as the number of seconds to wait for a response to an EAP-request/identity frame from the client before re-transmitting the request:

Switch(config-if)# dot1x timeout tx-period 60

You can verify your settings by entering the show dot1x privileged EXEC command.

Related Commands

Command
Description

dot1x max-req

Sets the maximum number of times that the switch sends an EAP-request/identity frame before restarting the authentication process.

dot1x reauthentication

Enables periodic re-authentication of the client.

show dot1x

Displays 802.1X status for all interfaces.


duplex

Use the duplex interface configuration command to specify the duplex mode of operation for Gigabit Ethernet ports. Use the no form of this command to return the port to its default value.

duplex {auto | full}

no duplex

Syntax Description

auto

Enable automatic duplex configuration; port automatically detects whether it should run in full- or half-duplex mode, depending on the attached device mode.

full

Enable full-duplex mode.


Defaults

The default is auto.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

Certain ports can be configured to be either full duplex or half duplex. Applicability of this command depends on the device to which the switch is attached.

For Gigabit Ethernet ports, setting the port to auto has the same effect as specifying full if the attached device does not autonegotiate the duplex parameter.

If both ends of the line support autonegotiation, we highly recommend using the default autonegotiation settings. If one interface supports autonegotiation and the other end does not, configure duplex and speed on both interfaces; do use the auto setting on the supported side.

If the speed is set to auto, the switch negotiates with the device at the other end of the link for the speed setting and then forces the speed setting to the negotiated value. The duplex setting remains as configured on each end of the link, which could result in a duplex setting mismatch.

For 10/100/1000 Mbps ports, if both the speed and duplex are set to specific values, autonegotiation is disabled.


Caution Changing the interface speed and duplex mode configuration might shut down and reenable the interface during the reconfiguration.


Note For guidelines on setting the switch speed and duplex parameters, refer to the software configuration guide for this release.


Examples

This example shows how to configure an interface for full duplex operation:

Switch(config)# interface gigabitethernet0/1
Switch(config-if)# duplex full

You can verify your setting by entering the show interfaces privileged EXEC command.

Related Commands

Command
Description

show interfaces

Displays the interface settings on the switch.

speed

Sets the speed on a 10/100/1000 Mbps interface.


errdisable detect cause

Use the errdisable detect cause global configuration command to enable error disable detection for a specific cause or all causes. Use the no form of this command to disable the error disable detection feature.

errdisable detect cause {all | dtp-flap | link-flap | loopback | pagp-flap}

no errdisable detect cause {all | dtp-flap | link-flap | pagp-flap}

Syntax Description

all

Enable error detection for all error-disable cases.

dtp-flap

Enable error detection for the Dynamic Trunking Protocol (DTP) flapping.

link-flap

Enable error detection for link-state flapping.

loopback

Enable error detection for detected loopbacks.

pagp-flap

Enable error detection for the Port Aggregation Protocol (PAgP) flap-error disable cause.



Note Though visible in the command-line help strings, the dhcp-rate-limit and gbic-invalid keywords are not supported.


Defaults

Detection is enabled for all causes.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

A cause (dtp-flap, link-flap, loopback, and pagp-flap) is the reason why the error-disabled state occurred. When a cause is detected on an interface, the interface is placed in an error-disabled state, an operational state similar to link-down state.

If you set a recovery mechanism for the cause by entering the errdisable recovery global configuration command for the cause, the interface is brought out of the error-disabled state and allowed to retry the operation when all causes have timed out. If you do not set a recovery mechanism, you must enter the shutdown and then the no shutdown commands to manually recover an interface from the error-disabled state.

Examples

This example shows how to enable error disable detection for the link-flap error-disable cause:

Switch(config)# errdisable detect cause link-flap

You can verify your setting by entering the show errdisable detect privileged EXEC command.

Related Commands

Command
Description

show errdisable detect

Displays errdisable detection information.

show interfaces status err-disabled

Displays interface status or a list of interfaces in the error-disabled state.


errdisable recovery

Use the errdisable recovery global configuration command to configure the recover mechanism variables. Use the no form of this command to return to the default setting.

errdisable recovery {cause {all | bpduguard | dtp-flap | link-flap | loopback | pagp-flap | psecure-violation | security-violation | udld | vmps} | {interval interval}

no errdisable recovery {cause {all | bpduguard | dtp-flap | link-flap | loopback | pagp-flap | psecure-violation | security-violation | udld | vmps} | {interval interval}

Syntax Description

cause

Enable error disable to recover from a specific cause.

all

Enable the timer to recover from all error-disable causes.

bpduguard

Enable the timer to recover from the bridge protocol data unit (BPDU) guard error-disable state.

dtp-flap

Enable the timer to recover from the Dynamic Trunking Protocol (DTP) flap error-disable state.

link-flap

Enable the timer to recover from the link-flap error-disable state.

loopback

Enable the timer to recover from a loopback error-disable state.

pagp-flap

Enable the timer to recover from the Port Aggregation Protocol (PAgP)-flap error-disable state.

psecure-violation

Enable the timer to recover from a port security violation disable state.

security-violation

Enable the timer to recover from an 802.1X violation disable state

udld

Enable the timer to recover from the UniDirectional Link Detection (UDLD) error-disable state.

vmps

Enable the timer to recover from the VLAN Membership Policy Server (VMPS) error-disable state.

interval interval

Specify the time to recover from the specified error-disable state. The range is 30 to 86400 seconds. The same interval is applied to all causes. The default interval is 300 seconds.

Note The errdisable recovery timer is initialized at a random differential from the configured interval value. The difference between the actual timeout value and the configured value can be up to 15 percent of the configured interval.



Note Though visible in the command-line help strings, the dhcp-rate-limit, unicast-flood, channel-misconfig, and gbic-invalid keywords are not supported.


Defaults

Recovery is disabled for all causes.

The default recovery interval is 300 seconds.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.

12.1(14)EA1

The security-violation keyword was added.


Usage Guidelines

A cause (bpduguard, dtp-flap, link-flap, loopback, pagp-flap, psecure-violation, security-violation, udld, vmps) is defined as the reason why the error-disabled state occurred. When a cause is detected on an interface, the interface is placed in error-disabled state, an operational state similar to link-down state. If you do not enable errdisable recovery for the cause, the interface stays in error-disabled state until you enter a shutdown and no shutdown interface configuration command. If you enable the recovery for a cause, the interface is brought out of the error-disabled state and allowed to retry the operation again when all the causes have timed out.

Otherwise, you must enter the shutdown then no shutdown commands to manually recover an interface from the error-disabled state.

Examples

This example shows how to enable the recovery timer for the BPDU guard error-disable cause:

Switch(config)# errdisable recovery cause bpduguard

This example shows how to set the timer to 500 seconds:

Switch(config)# errdisable recovery interval 500

You can verify your settings by entering the show errdisable recovery privileged EXEC command.

Related Commands

Command
Description

show errdisable recovery

Displays errdisable recovery timer information.

show interfaces status err-disabled

Displays interface status or a list of interfaces in error-disabled state.


flowcontrol

Use the flowcontrol interface configuration command to set the receive flow-control state for an interface. When flow control send is operable and on for a device and it detects any congestion at its end, it notifies the link partner or the remote device of the congestion by sending a pause frame. When flow control receive is on for a device and it receives a pause frame, it stops sending any data packets. This prevents any loss of data packets during the congestion period.

Use the receive off keywords to disable flow control.

flowcontrol receive {desired | off | on}


Note The Catalyst 2970 switch can only receive pause frames.


Syntax Description

receive

Sets whether the interface can receive flow-control packets from a remote device.

desired

Allows an interface to operate with an attached device that is required to send flow-control packets or with an attached device that is not required to but can send flow-control packets.

off

Turns off an attached device's ability to send flow-control packets to an interface.

on

Allows an interface to operate with an attached device that is required to send flow-control packets or with an attached device that is not required to but can send flow-control packets.


Defaults

The default is flowcontrol receive off.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

The switch does not support sending flow-control pause frames.

Note that the on and desired keywords have the same result.

When you use the flowcontrol command to set a port to control traffic rates during congestion, you are setting flow control on a port to one of these conditions:

receive on or desired: The port cannot send out pause frames, but can operate with an attached device that is required to or is able to send pause frames; the port is able to receive pause frames.

receive off: Flow control does not operate in either direction. In case of congestion, no indication is given to the link partner and no pause frames are sent or received by either device.

Table 2-5 shows the flow control results on local and remote ports for a combination of settings. The table assumes that receive desired has the same results as using the receive on keywords.

Table 2-5 Flow Control Settings and Local and Remote Port Flow Control Resolution 

Flow Control Settings
Flow Control Resolution
Local Device
Remote Device
Local Device
Remote Device

send off/receive on

send on/receive on

send on/receive off

send desired/receive on

send desired/receive off

send off/receive on

send off/receive off

Receives only

Receives only

Receives only

Receives only

Receives only

Does not send or receive

Sends and receives

Sends only

Sends and receives

Sends only

Receives only

Does not send or receive

send off/receive off

send on/receive on

send on/receive off

send desired/receive on

send desired/receive off

send off/receive on

send off/receive off

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive

Does not send or receive


Examples

This example shows how to configure the local port to not support flow control by the remote port:

Switch(config-if)# flowcontrol receive off

You can verify your settings by entering the show interfaces privileged EXEC command.

Related Commands

Command
Description

show interfaces

Displays the interface settings on the switch, including input and output flow control.


interface port-channel

Use the interface port-channel global configuration command to access or create the port-channel logical interface. Use the no form of this command to remove the port-channel.

interface port-channel port-channel-number

no interface port-channel port-channel-number

Syntax Description

port-channel-number

Port-channel number. The range is 1 to12.


Defaults

No port-channel logical interfaces are defined.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

For Layer 2 EtherChannels, you do not have to create a port-channel interface first before assigning a physical interface to a channel group. Instead, you can use the channel-group interface configuration command. It automatically creates the port-channel interface when the channel group gets its first physical interface. If you create the port-channel interface first, the channel-group-number can be the same as the port-channel-number, or you can use a new number. If you use a new number, the channel-group command dynamically creates a new port channel.

Only one port channel in a channel group is allowed.

Follow these guidelines when you use the interface port-channel command:

If you want to use the Cisco Discovery Protocol (CDP), you must configure it only on the physical interface and not on the port-channel interface.

Do not configure a port that is an active member of an EtherChannel as an 802.1X port. If 802.1X is enabled on a not-yet active port of an EtherChannel, the port does not join the EtherChannel.

For a complete list of configuration guidelines, refer to the "Configuring EtherChannels" chapter in the software guide for this release.

Examples

This example shows how to create a port-channel interface with a port channel number of 5:

Switch(config)# interface port-channel 5

You can verify your setting by entering the show running-config privileged EXEC or show etherchannel channel-group-number detail privileged EXEC command.

Related Commands

Command
Description

channel-group

Assigns an Ethernet interface to an EtherChannel group.

show etherchannel

Displays EtherChannel information for a channel.

show running-config

Displays the current operating configuration. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


interface range

Use the interface range global configuration command to enter interface range configuration mode and to execute a command on multiple ports at the same time. Use the no form of this command to remove an interface range.

interface range {port-range | macro name}

no interface range {port-range | macro name}

Syntax Description

port-range

Port range. For a list of valid values for port-range, see the "Usage Guidelines" section.

macro name

Specify the name of a macro.


Defaults

This command has no default setting.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

When you enter interface range configuration mode, all interface parameters you enter are attributed to all interfaces within the range.

For VLANs, you can use the interface range command only on existing VLAN switch virtual interfaces (SVIs). To display VLAN SVIs, enter the show running-config privileged EXEC command. VLANs not displayed cannot be used in the interface range command. The commands entered under interface range command are applied to all existing VLAN SVIs in the range.

All configuration changes made to an interface range are saved to nonvolatile RAM (NVRAM), but the interface range itself is not saved to NVRAM.

You can enter the interface range in two ways:

Specifying up to five interface ranges

Specifying a previously defined interface-range macro

All interfaces in a range must be the same type; that is, all Gigabit Ethernet ports, all EtherChannel ports, or all VLANs. However, you can define up to five interface ranges with a single command, with each range separated by a comma.

Valid values for port-range type and interface:

vlan vlan-ID - vlan-ID, where VLAN ID is from 1 to 4094

gigabitethernet module/{first port} - {last port}, where module is 0

For physical interfaces:

module is always 0

the range is type 0/number - number (for example, gigabitethernet0/1 - 2)

port-channel port-channel-number - port-channel-number, where port-channel-number is from 1 to 12


Note When you use the interface range command with port channels, the first and last port channel number in the range must be active port channels.


When you define a range, you must enter a space between the first entry and the hyphen (-):

interface range gigabitethernet0/1 -2

When you define multiple ranges, you must still enter a space after the first entry, before the comma (,):

interface range gigabitethernet0/3 -5, gigabitethernet0/7 -8

You cannot specify both a macro and an interface range in the same command.

A single interface can also be specified in port-range (this would make the command similar to the interface interface-id global configuration command).


Note For more information about configuring interface ranges, refer to the software configuration guide for this release.


Examples

This example shows how to use the interface range command to enter interface range configuration mode to apply commands to two ports:

Switch(config)# interface range gigabitethernet0/1 - 2
Switch(config-if-range)#

This example shows how to use a port-range macro macro1 for the same function. The advantage is that you can reuse macro1 until you delete it.

Switch(config)# define interface-range macro1 gigabitethernet0/1 - 2
Switch(config)# interface range macro macro1
Switch(config-if-range)#

Related Commands

Command
Description

define interface-range

Creates an interface range macro.

show running-config

Displays the configuration information currently running on the switch. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


interface vlan

Use the interface vlan global configuration command to create or access a VLAN and to enter interface configuration mode. Use the no form of this command to delete a VLAN.

interface vlan vlan-id

no interface vlan vlan-id

Syntax Description

vlan-id

VLAN number. The range is 1 to 4094.


Defaults

The default VLAN interface is VLAN 1.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You cannot delete the VLAN 1 interface.

VLANs are created the first time that you enter the interface vlan vlan-id command for a particular vlan. The vlan-id corresponds to the VLAN-tag associated with data frames on an ISL or 802.1Q encapsulated trunk or the VLAN ID configured for an access port.

If you delete a VLAN by entering the no interface vlan vlan-id command, the deleted interface is no longer visible in the output from the show interfaces privileged EXEC command.

You can reinstate a deleted VLAN by entering the interface vlan vlan-id command for the deleted interface. The interface comes back up, but much of the previous configuration will be gone.

Examples

This example shows how to create a new VLAN with VLAN ID 23 and enter interface configuration mode:

Switch(config)# interface vlan 23
Switch(config-if)#

You can verify your setting by entering the show interfaces and show interfaces vlan vlan-id privileged EXEC commands.

Related Commands

Command
Description

show interfaces vlan vlan-id

Displays the administrative and operational status of all interfaces or the specified VLAN.


ip access-group

Use the ip access-group interface configuration command to control access to a Layer 2 interface. Use the no form of this command to remove all access groups or the specified access group from the interface.

ip access-group {access-list-number | name} {in}

no ip access-group [access-list-number | name] {in}

Syntax Description

access-list-number

The number of the IP access control list (ACL). The range is 1 to 199 or 1300 to 2699.

name

The name of an IP ACL, specified in the ip access-list global configuration command.

in

Specify filtering on inbound packets.


Defaults

No access list is applied to the interface.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

You can apply named or numbered standard or extended IP access lists to an interface. To define an access list by name, use the ip access-list global configuration command. To define a numbered access list, use the access list global configuration command. You can used numbered standard access lists ranging from 1 to 99 and 1300 to 1999 or extended access lists ranging from 100 to 199 and 2000 to 2699.

You can use this command to apply an access list to a Layer 2 interface. However, note these limitations for port ACLs:

You can only apply ACLs in the inbound direction.

You can only apply one IP ACL and one MAC ACL per interface.

Port ACLs do not support logging; if the log keyword is specified in the IP ACL, it is ignored.

An IP ACL applied to an interface only filters IP packets. To filter non-IP packets, use the mac access-group interface configuration command with MAC extended ACLs.

You can use input port ACLs and VLAN maps on the same switch. However, a port ACL takes precedence over a VLAN map. When both an input port ACL and a VLAN map are applied, incoming packets received on ports with the port ACL applied are filtered by the port ACL. Other packets are filtered by the VLAN map.

For standard inbound access lists, after the switch receives a packet, it checks the source address of the packet against the access list. IP extended access lists can optionally check other fields in the packet, such as the destination IP address, protocol type, or port numbers. If the access list permits the packet, the switch continues to process the packet. If the access list denies the packet, the switch discards the packet.

If the specified access list does not exist, all packets are passed.

Examples

This example shows how to apply IP access list 101 to inbound packets on Gigabit Ethernet interface 0/1:

Switch(config)# interface gigabitethernet0/1
Switch(config-if)# ip access-group 101 in

You can verify your settings by entering the show ip interface, show access-lists, or show ip access-lists privileged EXEC command.

Related Commands

Command
Description

access list

Configures a numbered ACL. For syntax information, select Cisco IOS IP and IP Routing Command Reference for IOS Release 12.1 > IP Addressing and Services > IP Services Commands.

ip access-list

Configures a named ACL. For syntax information, select Cisco IOS IP and IP Routing Command Reference for IOS Release 12.1 > IP Addressing and Services > IP Services Commands.

show access-lists

Displays ACLs configured on the switch.

show ip access-lists

Displays IP ACLs configured on the switch. For syntax information, select Cisco IOS IP and IP Routing Command Reference for IOS Release 12.1 > IP Addressing and Services > IP Services Commands.

show ip interface

Displays information about interface status and configuration. For syntax information, select Cisco IOS IP and IP Routing Command Reference for IOS Release 12.1 > IP Addressing and Services > IP Addressing Commands.


ip address

Use the ip address interface configuration command to set an IP address for the Layer 2 switch. Use the no form of this command to remove an IP address or to disable IP processing.

ip address ip-address subnet-mask [secondary]

no ip address [ip-address subnet-mask] [secondary]

Syntax Description

ip-address

IP address.

subnet-mask

Mask for the associated IP subnet.

secondary

(Optional) Specifies that the configured address is a secondary IP address. If this keyword is omitted, the configured address is the primary IP address.


Defaults

No IP address is defined.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

If you remove the switch IP address through a Telnet session, your connection to the switch will be lost.

Hosts can determine subnet masks using the Internet Control Message Protocol (ICMP) Mask Request message. Routers respond to this request with an ICMP Mask Reply message.

You can disable IP processing on a particular interface by removing its IP address with the no ip address command. If the switch detects another host using one of its IP addresses, it will send an error message to the console.

You can use the optional keyword secondary to specify an unlimited number of secondary addresses. Secondary addresses are treated like primary addresses, except the system never generates datagrams other than routing updates with secondary source addresses. IP broadcasts and ARP requests are handled properly, as are interface routes in the IP routing table.


Note If any router on a network segment uses a secondary address, all other devices on that same segment must also use a secondary address from the same network or subnet. Inconsistent use of secondary addresses on a network segment can very quickly cause routing loops.


If your switch receives its IP address from a Bootstrap Protocol (BOOTP) or Dynamic Host Configuration Protocol (DHCP) server and you remove the switch IP address by using the no ip address command, IP processing is disabled, and the BOOTP or DHCP server cannot reassign the address.

Examples

This example shows how to configure the IP address for the Layer 2 switch on a subnetted network:

Switch(config)# interface vlan 1
Switch(config-if)# ip address 172.20.128.2 255.255.255.0

You can verify your settings by entering the show running-config privileged EXEC command.

Related Commands

Command
Description

show running-config

Displays the running configuration on the switch. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


ip igmp filter

Use the ip igmp filter interface configuration command to control whether or not all hosts on a Layer 2 interface can join one or more IP multicast groups by applying an Internet Group Management Protocol (IGMP) profile to the interface. Use the no form of this command to remove the specified profile from the interface.

ip igmp filter profile number

no ip igmp filter

Syntax Description

profile number

The IGMP profile number to be applied. The range is 1 to 4294967295.


Defaults

No IGMP filters are applied.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You can apply IGMP filters only to Layer 2 physical interfaces; you cannot apply IGMP filters to ports that belong to an EtherChannel group.

An IGMP profile can be applied to one or more switch port interfaces, but one port can have only one profile applied to it.

Examples

This example shows how to apply IGMP profile 22 to an interface.

Switch(config)# interface gigabitethernet0/12
Switch(config-if)# ip igmp filter 22

You can verify your setting by using the show running-config privileged EXEC command and by specifying an interface.

Related Commands

Command
Description

ip igmp profile

Configures the specified IGMP profile number.

show ip igmp profile

Displays the characteristics of the specified IGMP profile.

show running-config interface interface-id

Displays the running configuration on the switch interface, including the IGMP profile (if any) that is applied to an interface. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


ip igmp max-groups

Use the ip igmp max-groups interface configuration command to set the maximum number of Internet Group Management Protocol (IGMP) groups that a Layer 2 interface can join. Use the no form of this command to set the maximum back to the default, which is to have no maximum limit.

ip igmp max-groups number

no ip igmp max-groups

Syntax Description

number

The maximum number of IGMP groups that an interface can join. The range is 0 to 4294967294. The default is no limit.


Defaults

No limit.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You can use this command only on Layer 2 physical interfaces; you cannot set IGMP maximum groups for ports that belong to an EtherChannel group.

Examples

This example shows how to limit the number of IGMP groups that an interface can join to 25.

Switch(config)# interface gigabitethernet0/12
Switch(config-if)# ip igmp max-groups 25

You can verify your setting by using the show running-config privileged EXEC command and by specifying an interface.

Related Commands

Command
Description

show running-config interface interface-id

Displays the running configuration on the switch interface, including the maximum number of IGMP groups that an interface can join. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


ip igmp profile

Use the ip igmp profile global configuration command to create an Internet Group Management Protocol (IGMP) profile and enter IGMP profile configuration mode. From this mode, you can specify the configuration of the IGMP profile to be used for filtering IGMP membership reports from a switchport. Use the no form of this command to delete the IGMP profile.

ip igmp profile profile number

no ip igmp profile profile number

Syntax Description

profile number

The IGMP profile number being configured. The range is 1 to 4294967295.


Defaults

No IGMP profiles are defined. When configured, the default action for matching an IGMP profile is to deny matching addresses.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

When you are in IGMP profile configuration mode, you can create the profile by using these commands:

deny: specifies that matching addresses are denied; this is the default condition.

exit: exits from igmp-profile configuration mode.

no: negates a command or resets to its defaults.

permit: specifies that matching addresses are permitted.

range: specifies a range of IP addresses for the profile. This can be a single IP address or a range with a start and an end address.

When entering a range, enter the low IP multicast address, a space, and the high IP multicast address.

You can apply an IGMP profile to one or more Layer 2 interfaces, but each interface can have only one profile applied to it.

Examples

This example shows how to configure IGMP profile 40 that permits the specified range of IP multicast addresses.

Switch(config)# ip igmp profile 40
Switch(config-igmp-profile)# permit
Switch(config-igmp-profile)# range 233.1.1.1 233.255.255.255

You can verify your settings by using the show ip igmp profile privileged EXEC command.

Related Commands

Command
Description

ip igmp filter

Applies the IGMP profile to the specified interface.

show ip igmp profile

Displays the characteristics of all IGMP profiles or the specified IGMP profile number.


ip igmp snooping

Use the ip igmp snooping global configuration command to globally enable Internet Group Management Protocol (IGMP) snooping on the switch or to enable it on a VLAN. Use the command with keywords to enable and configure IGMP snooping on a VLAN interface. Use the no form of this command to disable IGMP snooping or to reset the parameters to the default settings.

ip igmp snooping [vlan vlan-id [immediate-leave | mrouter {interface interface-id | learn {cgmp | pim-dvmrp}} | static ip-address interface interface-id]]

no ip igmp snooping [vlan vlan-id [immediate-leave | mrouter {interface interface-id | learn {cgmp | pim-dvmrp}} | static ip-address interface interface-id]]

Syntax Description

vlan vlan-id

(Optional) When used with other keywords, enable IGMP snooping on a VLAN interface. Use the no form of this command to disable IGMP snooping on a VLAN interface. The range is 1 to 4094.

immediate-leave

(Optional) Enable IGMP immediate-leave processing on a VLAN interface. Use the no form of the command to disable the Immediate Leave feature on the interface.

mrouter

(Optional) Add a multicast router port or configure the multicast router learning method. The no form of the command removes the configuration.

interface interface-id

(Optional) With mrouter, specify the next-hop interface to the multicast router.

With static, specify the interface of the member port. It can be one of these values:

gigabitethernet interface number—a Gigabit Ethernet 802.3Z interface.

port-channel interface number—a channel interface. The range is 0 to 12.

learn

(Optional) With mrouter, specify the multicast router learning method.

cgmp

Set the switch to learn multicast router ports by snooping on Cisco Group Management Protocol (CGMP) packets.

pim-dvmrp

Set the switch to learn multicast router ports by snooping on IGMP queries and Protocol-Independent Multicast-Distance Vector Multicast Routing Protocol (PIM-DVMRP) packets.

static ip-address

(Optional) Add a Layer 2 port as a member of a multicast group with the specified group IP address.



Note Though visible in the command-line help string, the report-suppression, source-only-learning, and tcn keywords are not supported.


Defaults

IGMP snooping is globally enabled on the switch.

IGMP snooping is enabled on VLAN interfaces.

IGMP immediate-leave processing is disabled.

The default learning method is pim-dvmrp—to snoop IGMP queries and PIM-DVMRP packets.

By default, there are no ports specified as members of a static multicast group.

By default, there are no multicast router ports.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

When IGMP snooping is enabled globally, it is enabled in all the existing VLAN interfaces. When IGMP snooping is disabled globally, it is disabled on all the existing VLAN interfaces.

You should only configure the Immediate Leave feature when there is a maximum of one receiver on every port in the VLAN. The configuration is saved in nonvolatile RAM (NVRAM).

The Immediate Leave feature is supported only with IGMP version 2 hosts.

The CGMP learn method is useful for reducing control traffic.

The static keyword is used for configuring the IGMP member ports statically.

The enabled configuration (globally or per VLAN), the learn method, and the static ports and groups are saved in nonvolatile RAM (NVRAM).

Examples

This example shows how to globally enable IGMP snooping:

Switch(config)# ip igmp snooping

This example shows how to globally disable IGMP snooping:

Switch(config)# no ip igmp snooping

This example shows how to enable IGMP snooping on VLAN 1:

Switch(config)# ip igmp snooping vlan 1

This example shows how to disable IGMP snooping on VLAN 1:

Switch(config)# no ip igmp snooping vlan 1

This example shows how to enable IGMP immediate-leave processing on VLAN 1:

Switch(config)# ip igmp snooping vlan 1 immediate-leave

This example shows how to disable IGMP immediate-leave processing on VLAN 1:

Switch(config)# no ip igmp snooping vlan 1 immediate-leave

This example shows how to configure Gigabit Ethernet interface 2 as a multicast router port:

Switch(config)# ip igmp snooping vlan 1 mrouter interface gigabitethernet0/2

This example shows how to specify the multicast router learning method as CGMP:

Switch(config)# no ip igmp snooping vlan 1 mrouter learn cgmp

You can verify your settings by entering the show ip igmp snooping privileged EXEC command.

Related Commands

Command
Description

show ip igmp snooping

Displays the snooping configuration.

show ip igmp snooping mrouter

Displays the IGMP snooping router ports.

show ip igmp snooping multicast

Displays IGMP snooping multicast information.


lacp port-priority

Use the lacp port-priority interface configuration command to configure the port priority for the Link Aggregation Control Protocol (LACP). Use the no form of this command to return to the default setting.

lacp port-priority priority

no lacp port-priority

Syntax Description

priority

Port priority for LACP. The range is 1 to 65535.


Defaults

The default is 32768.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

This command takes effect only on EtherChannel interfaces that are already configured for LACP.

The software assigns to every link between systems that operate LACP a unique priority made up of the system priority, system ID, port priority, and the port number. In priority comparisons, numerically lower values have higher priority. The priority determines which ports should be put in standby mode when there is a hardware limitation that prevents all compatible ports from aggregating.

Ports are considered for active use in aggregation in link-priority order starting with the port attached to the highest priority link. Each port is selected for active use if the preceding higher priority selections can also be maintained. Otherwise, the port is selected for standby mode. Use the show etherchannel summary privileged EXEC command to see which ports are in the hot-standby mode (denoted with an H port-state flag).

The lower the priority, the more likely that the interface will be used for LACP transmission.

For information about configuring LACP on physical interfaces, refer to the "Configuring EtherChannels" chapter in the software configuration guide for this release.

Examples

This example shows how to configure the LACP port priority on Gigabit Ethernet interface 0/1:

Switch(config)# interface gigabitethernet0/1
Switch(config-if)# lacp port-priority 1000

You can verify your settings by entering the show lacp [channel-group-number] internal privileged EXEC command.

Related Commands

Command
Description

channel-group

Assigns an Ethernet interface to an EtherChannel group.

lacp system-priority

Configures the LACP system priority.

show lacp [channel-group-number] internal

Displays internal information for all channel groups or for the specified channel group.


lacp system-priority

Use the lacp system-priority global configuration command to configure the system priority for the Link Aggregation Control Protocol (LACP). Use the no form of this command to return to the default setting.

lacp system-priority priority

no lacp system-priority

Syntax Description

priority

System priority for LACP. The range is 1 to 65535.


Defaults

The default is 32768.

Command Modes

Global configuration

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

Although this is a global configuration command, the priority takes effect only on EtherChannels that have physical interfaces that are already configured for LACP.

The software assigns to every link between systems that operate LACP a unique priority made up of the system priority, system ID, port priority, and the port number. In priority comparisons, numerically lower values have higher priority. The priority determines which ports should be put in standby mode when there is a hardware limitation that prevents all compatible ports from aggregating.

Ports are considered for active use in aggregation in link-priority order, starting with the port attached to the highest priority link. Each port is selected for active use if the preceding higher priority selections can also be maintained. Otherwise, the port is selected for standby mode. Use the show etherchannel summary privileged EXEC command to see which ports are in the hot-standby mode (denoted with an H port-state flag).

The lower the priority, the more likely that the interface will be used for LACP transmission.

For more information about configuring LACP on physical interfaces, refer to the "Configuring EtherChannels" chapter in the software configuration guide for this release.

Examples

This example shows how to set the LACP system priority:

Switch(config)# lacp system-priority 20000

You can verify your settings by entering the show lacp sys-id privileged EXEC command.

Related Commands

Command
Description

channel-group

Assigns an Ethernet interface to an EtherChannel group.

lacp port-priority

Configures the LACP port priority.

show lacp sys-id

Display the system identifier that is being used by LACP.


logging file

Use the logging file global configuration command to set logging file parameters. Use the no form of this command to return to the default setting.

logging file filesystem:filename [max-file-size [min-file-size]] [severity-level-number | type]

no logging file filesystem:filename [severity-level-number | type]

Syntax Description

filesystem:filename

Alias for a Flash file system. Contains the path and name of the file that contains the log messages.

The syntax for the local Flash file system:
flash:

max-file-size

(Optional) Specify the maximum logging file size. The range is 4096 to 2147483647.

min-file-size

(Optional) Specify the minimum logging file size. The range is 1024 to 2147483647.

severity-level-number

(Optional) Specify the logging severity level. The range is 0 to 7. See the type option for the meaning of each level.

type

(Optional) Specify the logging type. These keywords are valid:

emergencies—System is unusable (severity 0).

alerts—Immediate action needed (severity 1).

critical—Critical conditions (severity 2).

errors—Error conditions (severity 3).

warnings—Warning conditions (severity 4).

notifications—Normal but significant messages (severity 5).

information—Information messages (severity 6).

debugging—Debugging messages (severity 7).


Defaults

The minimum file size is 2048 bytes; the maximum file size is 4096 bytes.

The default severity level is 7 (debugging messages and numerically lower levels).

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

The log file is stored in ASCII text format in an internal buffer on the switch. You can access logged system messages by using the switch command-line interface (CLI) or by saving them to a properly configured syslog server. If the switch fails, the log is lost unless you had previously saved it to Flash memory by using the logging file flash:filename global configuration command.

After saving the log to Flash memory by using the logging file flash:filename global configuration command, you can use the more flash:filename privileged EXEC command to display its contents.

The command rejects the minimum file size if it is greater than the maximum file size minus 1024; the minimum file size then becomes the maximum file size minus 1024.

Specifying a level causes messages at that level and numerically lower levels to be displayed.

Examples

This example shows how to save informational log messages to a file in Flash memory:

Switch(config)# logging file flash:logfile informational

You can verify your setting by entering the show running-config privileged EXEC command.

Related Commands

Command
Description

show running-config

Displays the running configuration on the switch. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


mac access-group

Use the mac access-group interface configuration command to apply a MAC access control list (ACL) to a Layer 2 interface. Use the no form of this command to remove all MAC ACLs or the specified MAC ACL from the interface. You create the MAC ACL by using the mac access-list extended global configuration command.

mac access-group {name} in

no mac access-group {name}

Syntax Description

name

Specify a named MAC access list.

in

Specify that the ACL is applied in the ingress direction. Outbound ACLs are not supported on Layer 2 interfaces.


Defaults

No MAC ACL is applied to the interface.

Command Modes

Interface configuration (Layer 2 interfaces only)

Command History

Release
Modification

12.1(14)EA1

This command was first introduced.


Usage Guidelines

You can apply MAC ACLs only to ingress Layer 2 interfaces.

On Layer 2 interfaces, you can filter IP traffic by using IP access lists and non-IP traffic by using MAC access lists. You can filter both IP and non-IP traffic on the same Layer 2 interface by applying both an IP ACL and a MAC ACL to the interface. You can apply no more than one IP access list and one MAC access list to the same Layer 2 interface.

If a MAC ACL is already configured on a Layer 2 interface and you apply a new MAC ACL to the interface, the new ACL replaces the previously configured one.

If you apply an ACL to a Layer 2 interface on a switch, and the switch has a VLAN map applied to a VLAN that the interface is a member of, the ACL applied to the Layer 2 interface takes precedence.

When an inbound packet is received on an interface with a MAC ACL applied, the switch checks the match conditions in the ACL. If the conditions are matched, the switch forwards or drops the packet, according to the ACL.

If the specified ACL does not exist, the switch forwards all packets.


Note For more information about configuring MAC extended ACLs, refer to the "Configuring Network Security with ACLs" chapter in the software configuration guide for this release.


Examples

This example shows how to apply a MAC extended ACL named macacl2 to an interface:

Switch(config)# interface gigabitethernet0/1
Switch(config-if)# mac access-group macacl2 in

You can verify your settings by entering the show mac access-group privileged EXEC command. You can view configured ACLs on the switch by entering the show access-lists privileged EXEC command.

Related Commands

Command
Description

show access-lists

Displays the ACLs configured on the switch.

show mac access-group

Displays the MAC ACLs configured on the switch.

show running-config

Displays the running configuration on the switch. For syntax information, select Cisco IOS Configuration Fundamentals Command Reference for Release 12.1 > Cisco IOS File Management Commands > Configuration File Commands.


mac access-list extended

Use the mac access-list extended global configuration command to create an access list based on MAC addresses for non-IP traffic. Using this command puts you in the extended MAC access list configuration mode. Use the no form of this command to return to the default setting.

mac access-list extended name

no mac access-list extended name

Syntax Description

name

Assign a name to the MAC extended access list.


Defaults

By default, there are no MAC access lists created.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

MAC named extended lists are used with VLAN maps and class maps.

You can apply named MAC extended ACLs to VLAN maps or to Layer 2 interfaces.

Entering the mac access-list extended command enables the MAC-access list configuration mode. These configuration commands are available:

default: sets a command to its default.

deny: specifies packets to reject. For more information, see the deny MAC-access list configuration command.

exit: exits from MAC-access list configuration mode.

no: negates a command or sets its defaults.

permit: specifies packets to forward. For more information, see the permit command.


Note For more information about MAC extended access lists, refer to the software configuration guide for this release.


Examples

This example shows how to create a MAC named extended access list named mac1 and to enter extended MAC access list configuration mode:

Switch(config)# mac access-list extended mac1
Switch(config-ext-macl)#

This example shows how to delete MAC named extended access list mac1:

Switch(config)# no mac access-list extended mac1

You can verify your settings by entering the show access-lists privileged EXEC command.

Related Commands

Command
Description

deny

permit

Configures the MAC ACL (in extended MAC-access list configuration mode).

show access-lists

Displays the access lists configured on the switch.

vlan access-map

Defines a VLAN map and enters access-map configuration mode where you can specify a MAC ACL to match and the action to be taken.


mac-address-table aging-time

Use the mac-address-table aging-time global configuration command to set the length of time that a dynamic entry remains in the MAC address table after the entry is used or updated. Use the no form of this command to return to the default setting. The aging time applies to all VLANs or a specified VLAN.

mac-address-table aging-time {0 | 10-1000000} [vlan vlan-id]

no mac-address-table aging-time {0 | 10-1000000} [vlan vlan-id]

Syntax Description

0

This value disables aging. Static address entries are never aged or removed from the table.

10-1000000

Aging time in seconds. The range is 10 to 1000000 seconds.

vlan vlan-id

(Optional) Specify the VLAN ID to which to apply the aging time. The range is 1 to 4094.


Defaults

The default is 300 seconds.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

If hosts do not send continuously, increase the aging time to record the dynamic entries for a longer time. Increasing the time can reduce the possibility of flooding when the hosts send again.

If you do not specify a specific VLAN, this command sets the aging time for all VLANs.

Examples

This example shows how to set the aging time to 200 seconds for all VLANs:

Switch(config)# mac-address-table aging-time 200

You can verify your setting by entering the show mac-address-table aging-time privileged EXEC command.

Related Commands

Command
Description

show mac-address-table aging-time

Displays the MAC address table aging time for all VLANs or the specified VLAN.


mac-address-table notification

Use the mac-address-table notification global configuration command to enable the MAC address notification feature on the switch. Use the no form of this command to return to the default setting.

mac-address-table notification [history-size value] | [interval value]

no mac-address-table notification [history-size | interval]

Syntax Description

history-size value

(Optional) Configure the maximum number of entries in the MAC notification history table. The range is 1 to 500 entries.

interval value

(Optional) Set the notification trap interval. The switch sends the notification traps when this amount of time has elapsed. The range is 0 to 2147483647 seconds.


Defaults

By default, the MAC address notification feature is disabled.

The default trap interval value is 1 second.

The default number of entries in the history table is 1.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

The MAC address notification feature sends Simple Network Management Protocol (SNMP) traps to the network management system (NMS) whenever a new MAC address is added or an old address is deleted from the forwarding tables. MAC notifications are generated only for dynamic and secure MAC addresses. Events are not generated for self addresses, multicast addresses, or other static addresses.

When you configure the history-size option, the existing MAC address history table is deleted, and a new table is created.

You enable the MAC address notification feature by using the mac-address-table notification command. You must also enable MAC address notification traps on an interface by using the snmp trap mac-notification interface configuration command and configure the switch to send MAC address traps to the NMS by using the snmp-server enable traps mac-notification global configuration command.

Examples

This example shows how to enable the mac-address-table notification feature, set the interval time to 60 seconds, and set the history-size to 100 entries:

Switch(config)# mac-address-table notification
Switch(config)# mac-address-table notification interval 60 
Switch(config)# mac-address-table notification history-size 100

You can verify your settings by entering the show mac-address-table notification privileged EXEC command.

Related Commands

Command
Description

clear mac-address-table notification

Clears the MAC address notification global counters.

show mac-address-table notification

Displays the MAC address notification settings on all interfaces or on the specified interface.

snmp-server enable traps

Sends the SNMP MAC notification traps when the mac-notification keyword is appended.

snmp trap mac-notification

Enables the SNMP MAC notification trap on a specific interface.


mac-address-table static

Use the mac-address-table static global configuration command to add static addresses to the MAC address table. Use the no form of this command to remove static entries from the table.

mac-address-table static mac-addr vlan vlan-id interface interface-id

no mac-address-table static mac-addr vlan vlan-id interface interface-id

Syntax Description

mac-addr

Destination MAC address (unicast or multicast) to add to the address table. Packets with this destination address received in the specified VLAN are forwarded to the specified interface.

vlan vlan-id

Specify the VLAN for which the packet with the specified MAC address is received. The range is 1 to 4094.

interface interface-id

Interface to which the received packet is forwarded. Valid interfaces include physical ports and port channels.


Defaults

No static addresses are configured.

Command Modes

Global configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Examples

This example shows how to add the static address c2f3.220a.12f4 to the MAC address table. When a packet is received in VLAN 4 with this MAC address as its destination, the packet is forwarded to the specified interface:

Switch(config)# mac-address-table static c2f3.220a.12f4 vlan 4 interface 
gigabitethernet0/1

You can verify your setting by entering the show mac-address-table privileged EXEC command.

Related Commands

Command
Description

show mac-address-table static

Displays static MAC address table entries only.


match (access-map configuration)

Use the match access-map configuration command to set the VLAN map to match packets against one or more access lists. Use the no form of this command to remove the match parameters.

match {ip address {name | number} [name | number] [name | number]...} | {mac address {name} [name] [name]...}

no match {ip address {name | number} [name | number] [name | number]...} | {mac address {name} [name] [name]...}

Syntax Description

ip address

Set the access map to match packets against an IP address access list.

mac address

Set the access map to match packets against a MAC address access list.

name

Name of the access list to match packets against.

number

Number of the access list to match packets against. This option is not valid for MAC access lists.


Defaults

The default action is to have no match parameters applied to a VLAN map.

Command Modes

Access-map configuration

Command History

Release
Modification

12.1(11)AX

This command was first introduced.


Usage Guidelines

You enter access-map configuration mode by using the vlan access-map global configuration command.

You must enter one access list name or number; others are optional. You can match packets against one or more access lists. Matching any of the lists counts as a match of the entry.

In access-map configuration mode, use the match command to define the match conditions for a VLAN map applied to a VLAN. Use the action command to set the action that occurs when the packet matches the conditions.

Packets are matched only against access lists of the same protocol type; IP packets are matched against IP access lists, and all other packets are matched against MAC access lists.

Both IP and MAC addresses can be specified for the same map entry.

Examples

This example shows how to define and apply a VLAN access map vmap4 to VLANs 5 and 6 that will cause the interface to drop an IP packet if the packet matches the conditions defined in access list al2.

Switch(config)# vlan access-map vmap4
Switch(config-access-map)# match ip address al2
Switch(config-access-map)# action drop
Switch(config-access-map)# exit
Switch(config)# vlan filter vmap4 vlan-list 5-6

You can verify your settings by entering the show vlan access-map privileged EXEC command.

Related Commands

Command
Description